Showing posts with label benefits. Show all posts
Showing posts with label benefits. Show all posts
9 Amazing Benefits of peas
Tuesday, May 20, 2014
9 Amazing Benefits of peas - Indonesian society is certainly familiar with peas. Vegetables are filled with starch is one vegetable that can grow quickly and easily developed. Legumes are usually mixed with other dishes in addition, whereas this one vegetable has abundant health benefits.
Do not believe? Here are some of the health benefits of peas, as reported by Boldsky.
1. Lower cholesterol
With peas you can congratulate high on bad cholesterol in the body. One of the health benefits of peas are lowering bad cholesterol levels and increase the amount of good cholesterol in the blood.
2. Constipation
Constipation is usually caused by lack of fiber and when you eat foods that are less attacking. eating peas that contain a lot of fiber will help you overcome constipation and facilitate digestion.
3. Heart health
Legumes can also help prevent heart disease. Legumes contain anti- inflammatory substances and several types of antioxidants that can help maintain heart health and prevent heart disease.
4. Lose weight
You are struggling to keep the weight off so as not to go up? Eating peas! Peas can help you lose weight because it has a low fat content. But do not forget to exercise diligently, not only to eat peas.
5. Ageless
Antioxidants in peas will help you stay young. This is because the levels of flavonoids, phytonutrients, carotenoids, and phenolic acids in it. The content of the peas that will keep you energized and youthful.
6. Preventing Alzheimers
Alzheimers is a brain disease that causes memory loss and brain function. Anti- inflammatory ingredients contained in peas could help prevent Alzheimers coming. Eating peas can also help you ward off osteoporosis and bronchitis.
7. Controlling blood sugar
Protein and fiber found in legumes is not only good for digestion, but also to lower the level of sugar in the blood. If you have a problem with high blood sugar or easy jump, it could not hurt to eat more frequently peas.
8. Anti- cancer
Research shows that good peas to prevent stomach cancer. Eating two peas milligrams a day known to be effective against cancer. Why should taking drugs if natural ingredients that can help prevent cancer?
9. Rich in vitamin K
Legumes are also known to be rich in vitamin K and can provide super benefit for bones. These vegetables are good for warding off osteoporosis and helps maintain healthy bones elsewhere in the body.
Some of the benefits over the course makes you no doubt not to eat peas? Vegetables are packed with nutrients and protein, and vitamins in it is very useful not only for health but also for the beauty that makes you young.
Do not believe? Here are some of the health benefits of peas, as reported by Boldsky.
1. Lower cholesterol
With peas you can congratulate high on bad cholesterol in the body. One of the health benefits of peas are lowering bad cholesterol levels and increase the amount of good cholesterol in the blood.
2. Constipation
Constipation is usually caused by lack of fiber and when you eat foods that are less attacking. eating peas that contain a lot of fiber will help you overcome constipation and facilitate digestion.
3. Heart health
Legumes can also help prevent heart disease. Legumes contain anti- inflammatory substances and several types of antioxidants that can help maintain heart health and prevent heart disease.
4. Lose weight
You are struggling to keep the weight off so as not to go up? Eating peas! Peas can help you lose weight because it has a low fat content. But do not forget to exercise diligently, not only to eat peas.
5. Ageless
Antioxidants in peas will help you stay young. This is because the levels of flavonoids, phytonutrients, carotenoids, and phenolic acids in it. The content of the peas that will keep you energized and youthful.
6. Preventing Alzheimers
Alzheimers is a brain disease that causes memory loss and brain function. Anti- inflammatory ingredients contained in peas could help prevent Alzheimers coming. Eating peas can also help you ward off osteoporosis and bronchitis.
7. Controlling blood sugar
Protein and fiber found in legumes is not only good for digestion, but also to lower the level of sugar in the blood. If you have a problem with high blood sugar or easy jump, it could not hurt to eat more frequently peas.
8. Anti- cancer
Research shows that good peas to prevent stomach cancer. Eating two peas milligrams a day known to be effective against cancer. Why should taking drugs if natural ingredients that can help prevent cancer?
9. Rich in vitamin K
Legumes are also known to be rich in vitamin K and can provide super benefit for bones. These vegetables are good for warding off osteoporosis and helps maintain healthy bones elsewhere in the body.
Some of the benefits over the course makes you no doubt not to eat peas? Vegetables are packed with nutrients and protein, and vitamins in it is very useful not only for health but also for the beauty that makes you young.
Unloading 13 Benefits of Honey That Stored Inside
Sunday, May 18, 2014

13 Benefits of Pure Honey:
1. Nutrition Of Pure Honey
Did my friend that every one kilo of honey have 3280 calories or equal to 50 eggs or equal to 1.68 kilograms danging or equal to 5.5 cups of milk
2. Why Good For diet?
honey for dietsmadu have unique properties, honey as a sweetener is more easily absorbed by the body than sugar means more young honey into energy in the human body and this is because honey can be directly processed into sugar while still requiring glukogen enzin digestion in the intestine, now to her diet secrets is the fact that honey is 40 percent lower in calories than sugar giving energy even larger than granulated sugar so that the honey does not lead to 40 percent more weight than sugar.
3. Easily digested by the most sensitive stomachs
this is one of the unique honey, although honey has a high acidity but easy to be accepted by the stomach for even the most sensitive stomachs, even honey can help the intestines and kidneys to be able to work better.
4. 7 minutes it takes honey to be energy
energijika honey as a source of our drinking honey with warm water then with just 7 minutes of honey
able to diffuse to the blood, this is one of the reasons why honey is so fast to increase stamina, not only that if we are tired and try to consume honey concentration decreases, because the free sugar is needed pengkomsumsi brain is the bodys largest sugar than other members.
5. Honey Acting As Blood Vessel Problems Prevention
honey has tremendous energy to be able to assist the process of blood formation, in addition to the honey helps the cleaning process as well as blood circulation, for this reason that the regular consumption of honey every day can prevent us against arteriosclerosis or vascular problems.
6. Honey As Anti Biotic
Honey is a natural antibiotic that serves to protect the body from pathogens, there are four reasons why the honey acts as an antibiotic.
> First of all, sugar has a high sugar content, it is causing bacteria can not thrive.
> Second reason, honey has a high ph causing pathogens it can not survive
> Third reason, honey has a pe-roksida hydrogen compounds that kill pathogenic microorganisms.
> The reason Fourth, honey has organic compounds that have anti-bacterial character among other glycosides, polyphenols, flavonoids.
. . . . . . . . . .
7 Health Benefits of Yoga
Saturday, May 17, 2014
7 Health Benefits of Yoga - Yoga is a meditation that originated in India. Yoga is centered on peace of mind so that it can be used as a kind of mental therapy for that run.
In addition to providing mental peace, it turns out the positive effects gained from yoga is also beneficial for physical health. Here are seven health benefits that you can get if you run a yoga regularly.
1. The balance of the brain
Ativitas yoga emphasizes balance and harmony on both sides of the brain. It can improve internal communication between the two brain that rarely can you do everyday. This will balance the internal communication between the brain and the brain thinking creatively.
2. Helpful for pregnancy
For those of you who are pregnant and want to continue to feel fit during pregnancy, do yoga every day. Yoga will help you to reduce fatigue and tension, improve muscle flexibility, and provide benefits to the digestive and respiratory. It also reduces pain during pregnancy such as leg cramps and lower back pain.
3. Streamlining respiratory
With the combination of a variety of movements and breathing techniques, yoga breathing can help smooth circulation and blood circulation in your body. With a smooth blood circulation, the oxygen flow in the body also will be smoother.
4. Flatten the stomach
Movements in yoga are named Naukasana and Ushtrasana based on the movement of sit ups. This movement will help you to flatten the stomach.
5. Healthy heart
With breathing and blood circulation smooth, then arteries and your heart be healthier. Yoga helps improve blood circulation as it will prevent blood clots.
6. Prevent aches and pains
Because yoga can increase flexibility and muscle strength, then yoga can also help you in preventing back pain and pain. It also can help you to improve the structure and posture for the better.
7. Reduce stress
With diligent practice, yoga can help you in relieving stress. It is thanks to the tranquility that you earn during yoga meditation.
Yoga was not only good for your mental health, but also can provide physical health. It would not hurt for you to start trying the art of meditation from India.
In addition to providing mental peace, it turns out the positive effects gained from yoga is also beneficial for physical health. Here are seven health benefits that you can get if you run a yoga regularly.
1. The balance of the brain
Ativitas yoga emphasizes balance and harmony on both sides of the brain. It can improve internal communication between the two brain that rarely can you do everyday. This will balance the internal communication between the brain and the brain thinking creatively.
2. Helpful for pregnancy
For those of you who are pregnant and want to continue to feel fit during pregnancy, do yoga every day. Yoga will help you to reduce fatigue and tension, improve muscle flexibility, and provide benefits to the digestive and respiratory. It also reduces pain during pregnancy such as leg cramps and lower back pain.
3. Streamlining respiratory
With the combination of a variety of movements and breathing techniques, yoga breathing can help smooth circulation and blood circulation in your body. With a smooth blood circulation, the oxygen flow in the body also will be smoother.
4. Flatten the stomach
Movements in yoga are named Naukasana and Ushtrasana based on the movement of sit ups. This movement will help you to flatten the stomach.
5. Healthy heart
With breathing and blood circulation smooth, then arteries and your heart be healthier. Yoga helps improve blood circulation as it will prevent blood clots.
6. Prevent aches and pains
Because yoga can increase flexibility and muscle strength, then yoga can also help you in preventing back pain and pain. It also can help you to improve the structure and posture for the better.
7. Reduce stress
With diligent practice, yoga can help you in relieving stress. It is thanks to the tranquility that you earn during yoga meditation.
Yoga was not only good for your mental health, but also can provide physical health. It would not hurt for you to start trying the art of meditation from India.
4 This Groceries have unexpected health benefits
Friday, May 9, 2014
4 This Groceries have unexpected health benefits - Vinegar not only can be used as a cooking ingredient. Likewise yogurt that it can make the skin look fresh. How can that be? Try to see the various uses of food and materials for the kitchen unexpected health as reported by the Health following.
Vinegar
Skin burned by the sun? Try to placate with vinegar. The trick, soak cotton wool in vinegar and rub gently on the burned skin.
Lemon
Being lethargic and not excited? Come smell the lemons! Research has shown that lemon aromatherapy can improve mood.
Yogurt
Yogurt is not only delicious and nutritious to be enjoyed. But food can also be used as a face mask. As a result, the skin will appear smoother and fresher.
Chamomile tea
Skin irritation can also be overcome with chamomile flower tea. The trick, soak the cloth in chamomile tea and compress the skin irritation.
Thats the variety of uses of food and kitchen materials for health unpredictable. Good work!
Vinegar
Skin burned by the sun? Try to placate with vinegar. The trick, soak cotton wool in vinegar and rub gently on the burned skin.
Lemon
Being lethargic and not excited? Come smell the lemons! Research has shown that lemon aromatherapy can improve mood.
Yogurt
Yogurt is not only delicious and nutritious to be enjoyed. But food can also be used as a face mask. As a result, the skin will appear smoother and fresher.
Chamomile tea
Skin irritation can also be overcome with chamomile flower tea. The trick, soak the cloth in chamomile tea and compress the skin irritation.
Thats the variety of uses of food and kitchen materials for health unpredictable. Good work!
Health Benefits of Coffee Updated
Thursday, May 8, 2014
I began using coffee a few months ago before soccer games (see Using Caffeine to Improve Athletic Performance) but have stepped up using it recently as I read about its health benefits. The review below of research on those benefits leaves be wondering why I did not start much earlier, and inspires me to step it up now:
Update:
Coffee consumption reduces risk of liver cancer
Coffee may help lower stroke risk
As coffee drinking increased, the risk of death decreased
Four or more cups of coffee a day may keep prostate cancer recurrence and progression away
Consuming Coffee = Lower Risk of Liver Disease
Coffee may help prevent breast cancer returning
Caffeinated coffee may reduce the risk of oral cancers
Moderate coffee consumption may reduce risk of diabetes by up to 25 percent
Original report:
Coffee consumption lowers risk of most common form of skin cancer
Increasing the number of cups of caffeinated coffee you drink could lower your risk of developing the most common form of skin cancer, basal cell carcinoma, according to a study published in Cancer Research, a journal of the American Association for Cancer Research.
"Our data indicate that the more caffeinated coffee you consume, the lower your risk of developing basal cell carcinoma," said Jiali Han, Ph.D., associate professor at Brigham and Womens Hospital, Harvard Medical School in Boston and Harvard School of Public Health.
"I would not recommend increasing your coffee intake based on these data alone," said Han. "However, our results add basal cell carcinoma to a list of conditions for which risk is decreased with increasing coffee consumption. This list includes conditions with serious negative health consequences such as type 2 diabetes and Parkinsons disease."
Basal cell carcinoma is the form of skin cancer most commonly diagnosed in the United States. Even though it is slow-growing, it causes considerable morbidity and places a burden on health care systems.
"Given the large number of newly diagnosed cases, daily dietary changes having any protective effect may have an impact on public health," said Han.
Han and his colleagues generated their results by conducting a prospective analysis of data from the Nurses Health Study, a large and long-running study to aid in the investigation of factors influencing womens health, and the Health Professionals Follow-up Study, an analogous study for men.
Of the 112,897 participants included in the analyses, 22,786 developed basal cell carcinoma during the more than 20 years of follow-up in the two studies. An inverse association was observed between all coffee consumption and risk of basal cell carcinoma. Similarly, an inverse association was seen between intake of caffeine from all dietary sources (coffee, tea, cola and chocolate) and risk of basal cell carcinoma. However, consumption of decaffeinated coffee was not associated with a decreased risk of basal cell carcinoma.
Moderate coffee consumption offers protection against heart failure
While current American Heart Association heart failure prevention guidelines warn against habitual coffee consumption, some studies propose a protective benefit, and still others find no association at all. Amidst this conflicting information, research from Beth Israel Deaconess Medical Center attempts to shift the conversation from a definitive yes or no, to a question of how much.
"Our results did show a possible benefit, but like with so many other things we consume, it really depends on how much coffee you drink," says lead author Elizabeth Mostofsky, MPH, ScD, a post-doctoral fellow in the cardiovascular epidemiological unit at BIDMC. "And compared with no consumption, the strongest protection we observed was at about four European, or two eight-ounce American, servings of coffee per day."
The study published June 26 online in the Journal Circulation: Heart Failure, found that these moderate coffee drinkers were at 11 percent lower risk of heart failure.
Data was analyzed from five previous studies – four conducted in Sweden, one in Finland – that examined the association between coffee consumption and heart failure. The self-reported data came from 140,220 participants and involved 6,522 heart failure events.
In a summary of the published literature, the authors found a "statistically significant J-shaped relationship" between habitual coffee consumption and heart failure, where protective benefits begin to increase with consumption maxing out at two eight-ounce American servings a day. Protection slowly decreases the more coffee is consumed until at five cups, there is no benefit and at more than five cups a day, there may be potential for harm.
Its unclear why moderate coffee consumption provides protection from heart failure, but the researchers say part of the answer may lie in the intersection between regular coffee drinking and two of the strongest risk factors for heart failure – diabetes and elevated blood pressure.
"There is a good deal of research showing that drinking coffee lowers the risk for type 2 diabetes, says senior author Murray Mittleman, MD, DrPH, a physician in the Cardiovascular Institute at Beth Israel Deaconess Medical Center, an Associate Professor of Medicine at Harvard Medical School and director of BIDMCs cardiovascular epidemiological research program. "It stands to reason that if you lower the risk of diabetes, you also lower the risk of heart failure."
There may also be a blood pressure benefit. Studies have consistently shown that light coffee and caffeine consumption are known to raise blood pressure. "But at that moderate range of consumption, people tend to develop a tolerance where drinking coffee does not pose a risk and may even be protective against elevated blood pressure," says Mittleman.
This study was not able to assess the strength of the coffee, nor did it look at caffeinated versus non-caffeinated coffee.
"There is clearly more research to be done," says Mostofsky. "But in the short run, this data may warrant a change to the guidelines to lect that coffee consumption, in moderation, may provide some protection from heart failure."
High blood caffeine levels linked to avoidance of Alzheimers disease
Those cups of coffee that you drink every day to keep alert appear to have an extra perk – especially if youre an older adult. A recent study monitoring the memory and thinking processes of people older than 65 found that all those with higher blood caffeine levels avoided the onset of Alzheimers disease in the two-to-four years of study follow-up. Moreover, coffee appeared to be the major or only source of caffeine for these individuals.
Researchers from the University of South Florida (www.usf.edu) and the University of Miami (www.miami.edu)say the case control study provides the first direct evidence that caffeine/coffee intake is associated with a reduced risk of dementia or delayed onset. Their findings will appear in the online version of an article to be published June 5 in the Journal of Alzheimers Disease, published by IOS Press (http://health.usf.edu/nocms/publicaffairs/now/pdfs/JAD111781.pdf). The collaborative study involved 124 people, ages 65 to 88, in Tampa and Miami.
"These intriguing results suggest that older adults with mild memory impairment who drink moderate levels of coffee -- about 3 cups a day -- will not convert to Alzheimers disease -- or at least will experience a substantial delay before converting to Alzheimers," said study lead author Dr. Chuanhai Cao, a neuroscientist at the USF College of Pharmacy (http://health.usf.edu/nocms/pharmacy/) and the USF Health Byrd Alzheimers Institute (http://health.usf.edu/nocms/byrd/). "The results from this study, along with our earlier studies in Alzheimers mice, are very consistent in indicating that moderate daily caffeine/coffee intake throughout adulthood should appreciably protect against Alzheimers disease later in life."
The study shows this protection probably occurs even in older people with early signs of the disease, called mild cognitive impairment, or MCI. Patients with MCI already experience some short-term memory loss and initial Alzheimers pathology in their brains. Each year, about 15 percent of MCI patients progress to full-blown Alzheimers disease. The researchers focused on study participants with MCI, because many were destined to develop Alzheimers within a few years.
Blood caffeine levels at the studys onset were substantially lower (51 percent less) in participants diagnosed with MCI who progressed to dementia during the two-to-four year follow-up than in those whose mild cognitive impairment remained stable over the same period.
No one with MCI who later developed Alzheimers had initial blood caffeine levels above a critical level of 1200 ng/ml – equivalent to drinking several cups of coffee a few hours before the blood sample was drawn. In contrast, many with stable MCI had blood caffeine levels higher than this critical level.
"We found that 100 percent of the MCI patients with plasma caffeine levels above the critical level experienced no conversion to Alzheimers disease during the two-to-four year follow-up period," said study co-author Dr. Gary Arendash.
The researchers believe higher blood caffeine levels indicate habitually higher caffeine intake, most probably through coffee. Caffeinated coffee appeared to be the main, if not exclusive, source of caffeine in the memory-protected MCI patients, because they had the same profile of blood immune markers as Alzheimers mice given caffeinated coffee. Alzheimers mice given caffeine alone or decaffeinated coffee had a very different immune marker profile.
Since 2006, USFs Dr. Cao and Dr. Arendash have published several studies investigating the effects of caffeine/coffee administered to Alzheimers mice. Most recently, they reported that caffeine interacts with a yet unidentified component of coffee to boost blood levels of a critical growth factor that seems to fight off the Alzheimers disease process.
"We are not saying that moderate coffee consumption will completely protect people from Alzheimers disease," Dr. Cao cautioned. "However, we firmly believe that moderate coffee consumption can appreciably reduce your risk of Alzheimers or delay its onset."
Alzheimers pathology is a process in which plaques and tangles accumulate in the brain, killing nerve cells, destroying neural connections, and ultimately leading to progressive and irreversible memory loss. Since the neurodegenerative disease starts one or two decades before cognitive decline becomes apparent, the study authors point out, any intervention to cut the risk of Alzheimers should ideally begin that far in advance of symptoms.
"Moderate daily consumption of caffeinated coffee appears to be the best dietary option for long-term protection against Alzheimers memory loss," Dr. Arendash said. "Coffee is inexpensive, readily available, easily gets into the brain, and has few side-effects for most of us. Moreover, our studies show that caffeine and coffee appear to directly attack the Alzheimers disease process."
In addition to Alzheimers disease, moderate caffeine/coffee intake appears to reduce the risk of several other diseases of aging, including Parkinsons disease, stroke, Type II diabetes, and breast cancer. However, supporting studies for these benefits have all been observational (uncontrolled), and controlled clinical trials are needed to definitively demonstrate therapeutic value.
A study tracking the health and coffee consumption of more than 400,000 older adults for 13 years, and published earlier this year in the New England Journal of Medicine, found that coffee drinkers reduced their risk of dying from heart disease, lung disease, pneumonia, stroke, diabetes, infections, and even injuries and accidents.
With new Alzheimers diagnostic guidelines encompassing the full continuum of the disease, approximately 10 million Americans now fall within one of three developmental stages of Alzheimers disease -- Alzheimers disease brain pathology only, MCI, or diagnosed Alzheimers disease. That number is expected to climb even higher as the baby-boomer generation continues to enter older age, unless an effective and proven preventive measure is identified.
"If we could conduct a large cohort study to look into the mechanisms of how and why coffee and caffeine can delay or prevent Alzheimers disease, it might result in billions of dollars in savings each year in addition to improved quality of life," Dr. Cao said.
Coffee drinkers have lower risk of death
Older adults who drank coffee -- caffeinated or decaffeinated -- had a lower risk of death overall than others who did not drink coffee, according a study by researchers from the National Cancer Institute (NCI), part of the National Institutes of Health, and AARP.
Coffee drinkers were less likely to die from heart disease, respiratory disease, stroke, injuries and accidents, diabetes, and infections, although the association was not seen for cancer. These results from a large study of older adults were observed after adjustment for the effects of other risk factors on mortality, such as smoking and alcohol consumption. Researchers caution, however, that they can’t be sure whether these associations mean that drinking coffee actually makes people live longer. The results of the study were published in the May 17, 2012, edition of the New England Journal of Medicine.
Neal Freedman, Ph.D., Division of Cancer Epidemiology and Genetics, NCI, and his colleagues examined the association between coffee drinking and risk of death in 400,000 U.S. men and women ages 50 to 71 who participated in the NIH-AARP Diet and Health Study. Information about coffee intake was collected once by questionnaire at study entry in 1995-1996. The participants were followed until the date they died or Dec. 31, 2008, whichever came first.
The researchers found that the association between coffee and reduction in risk of death increased with the amount of coffee consumed. Relative to men and women who did not drink coffee, those who consumed three or more cups of coffee per day had approximately a 10 percent lower risk of death. Coffee drinking was not associated with cancer mortality among women, but there was a slight and only marginally statistically significant association of heavier coffee intake with increased risk of cancer death among men.
“Coffee is one of the most widely consumed beverages in America, but the association between coffee consumption and risk of death has been unclear. We found coffee consumption to be associated with lower risk of death overall, and of death from a number of different causes,’’ said Freedman. “Although we cannot infer a causal relationship between coffee drinking and lower risk of death, we believe these results do provide some reassurance that coffee drinking does not adversely affect health.”
The investigators caution that coffee intake was assessed by self-report at a single time point and theore might not lect long-term patterns of intake. Also, information was not available on how the coffee was prepared (espresso, boiled, filtered, etc.); the researchers consider it possible that preparation methods may affect the levels of any protective components in coffee.
“The mechanism by which coffee protects against risk of death -- if indeed the finding lects a causal relationship -- is not clear, because coffee contains more than 1,000 compounds that might potentially affect health,’’ said Freedman. ``The most studied compound is caffeine, although our findings were similar in those who reported the majority of their coffee intake to be caffeinated or decaffeinated.”
Caffeine consumption = decreased risk of liver disease
Caffeine consumption has long been associated with decreased risk of liver disease and reduced fibrosis in patients with chronic liver disease. Now, newly published research confirms that coffee caffeine consumption reduces the risk of advanced fibrosis in those with nonalcoholic fatty liver disease (NAFLD). Findings published in the February, 2012 issue of Hepatology, a journal of the American Association for the Study of Liver Diseases, show that increased coffee intake, specifically among patients with nonalcoholic steatohepatitis (NASH), decreases risk of hepatic fibrosis.
The steady increase in rates of diabetes, obesity, and metabolic syndrome over the past 20 years has given rise to greater prevalence of NAFLD. In fact, experts now believe NAFLD is the leading cause of chronic liver disease in the U.S., surpassing both hepatitis B and C. The majority of patients will have isolated fatty liver which has a very low likelihood of developing progressive liver disease. However, a subset of patients will have NASH, which is characterized by inflammation of the liver, destruction of liver cells, and possibly scarring of the liver. Progression to cirrhosis (advanced scarring of the liver) may occur in about 10-11% of NASH patients over a 15 year period, although this is highly variable.
To enhance understanding of the correlation between coffee consumption and the prevalence and severity of NAFLD, a team led by Dr. Stephen Harrison, Lieutenant Colonel, U.S. Army at Brooke Army Medical Center in Fort Sam Houston, Texas surveyed participants from a previous NAFLD study as well as NASH patients treated at the centers hepatology clinic. The 306 participants were asked about caffeine coffee consumption and categorized into four groups: patients with no sign of fibrosis on ultrasound (control), steatosis, NASH stage 0-1, and NASH stage 2-4.
Researchers found that the average milligrams in total caffeine consumption per day in the control, steatosis, Nash 0-1, and Nash 2-4 groups was 307, 229, 351 and 252; average milligrams of coffee intake per day was 228, 160, 255, and 152, respectively. There was a significant difference in caffeine consumption between patients in the steatosis group compared to those with NASH stage 0-1. Coffee consumption was significantly greater for patients with NASH stage 0-1, with 58% of caffeine intake from regular coffee, than with NASH stage 2-4 patients at only 36% of caffeine consumption from regular coffee.
Multiple analyses showed a negative correlation between coffee consumption and risk of hepatic fibrosis. "Our study is the first to demonstrate a histopatholgic relationship between fatty liver disease and estimated coffee intake," concludes Dr. Harrison. "Patients with NASH may benefit from moderate coffee consumption that decreases risk of advanced fibrosis. Further prospective research should examine the amount of coffee intake on clinical outcomes."
Coffee may protect against endometrial cancer
Long-term coffee consumption may be associated with a reduced risk for endometrial cancer, according to a recent study in Cancer Epidemiology, Biomarkers & Prevention, a journal of the American Association for Cancer Research.
Edward Giovannucci, M.D., Sc.D., professor of nutrition and epidemiology at the Harvard School of Public Health, said coffee is emerging as a protective agent in cancers that are linked to obesity, estrogen and insulin.
"Coffee has already been shown to be protective against diabetes due to its effect on insulin," said Giovannucci, a senior researcher on the study. "So we hypothesized that wed see a reduction in some cancers as well."
Giovannucci, along with Youjin Je, a doctoral candidate in his lab, and colleagues observed cumulative coffee intake in relation to endometrial cancer in 67,470 women who enrolled in the Nurses Health Study.
During the course of 26 years of follow-up, researchers documented 672 cases of endometrial cancer.
Drinking more than four cups of coffee per day was linked with a 25 percent reduced risk for endometrial cancer. Drinking between two and three cups per day was linked with a 7 percent reduced risk.
A similar link was seen in decaffeinated coffee, where drinking more than two cups per day was linked with a 22 percent reduced risk for endometrial cancer.
Giovannucci said he hopes this study will lead to further inquiries about the effect of coffee on cancer because in this and similar studies, coffee intake is self-selected and not randomized.
"Coffee has long been linked with smoking, and if you drink coffee and smoke, the positive effects of coffee are going to be more than outweighed by the negative effects of smoking," said Giovannucci. "However, laboratory testing has found that coffee has much more antioxidants than most vegetables and fruits."
Increased Caffeinated Coffee Consumption Associated With Decreased Risk of Depression in Women
The risk of depression appears to decrease for women with increasing consumption of caffeinated coffee, according to a report in the September 26, 2011 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.
Caffeine is the most frequently used central nervous system stimulant in the world, and approximately 80 percent of consumption is in the form of coffee, according to background information in the article. Previous research, including one prospective study among men, has suggested an association between coffee consumption and depression risk. Because depression is a chronic and recurrent condition that affects twice as many women as men, including approximately one of every five U.S. women during their lifetime, “identification of risk factors for depression among women and the development of new preventive strategies are, theore, a public health priority,” write the authors. They sought to examine whether, in women, consumption of caffeine or certain caffeinated beverages is associated with the risk of depression.
Michel Lucas, Ph.D., R.D., from the Harvard School of Public Health, Boston, and colleagues studied 50,739 U.S. women who participated in the Nurses’ Health Study. Participants, who had a mean (average) age of 63, had no depression at the start of the study in 1996 and were prospectively followed up with through June 2006. Researchers measured caffeine consumption through questionnaires completed from May 1980 through April 2004, including the frequency that caffeinated and noncaffeinated coffee, nonherbal tea, caffeinated soft drinks (sugared or low-calorie colas), caffeine-free soft drinks (sugared or low-calorie caffeine-free colas or other carbonated beverages) and chocolate were usually consumed in the previous 12 months. The authors defined depression as reporting a new diagnosis of clinical depression and beginning regular use of antidepressants in the previous two years.
Analysis of the cumulative mean consumption included a two-year latency period; for example, data on caffeine consumption from 1980 through 1994 were used to predict episodes of clinical depression from 1996 through 1998; consumption from 1980 through 1998 were used for the 1998 through 2000 follow-up period; and so on. During the 10-year follow-up period from 1996 to 2006, researchers identified 2,607 incident (new-onset) cases of depression. When compared with women who consumed one cup of caffeinated coffee or less per week, those who consumed two to three cups per day had a 15 percent decrease in relative risk for depression, and those consuming four cups or more per day had a 20 percent decrease in relative risk. Compared with women in the lowest (less than 100 milligrams [mg] per day) categories of caffeine consumption, those in the highest category (550 mg per day or more) had a 20 percent decrease in relative risk of depression. No association was found between intake of decaffeinated coffee and depression risk.
“In this large prospective cohort of older women free of clinical depression or severe depressive symptoms at baseline, risk of depression decreased in a dose-dependent manner with increasing consumption of caffeinated coffee,” write the authors. They note that this observational study “cannot prove that caffeine or caffeinated coffee reduces the risk of depression but only suggests the possibility of such a protective effect.” The authors call for further investigations to confirm their results and to determine whether usual caffeinated coffee consumption could contribute to prevention or treatment of depre
Coffee Reduces Breast Cancer Risk
Recently published research shows that coffee drinkers enjoy not only the taste of their coffee but also a reduced risk of cancer with their cuppa. More detailed research published May 10, 2011 in BioMed Centrals open access journal Breast Cancer Research shows that drinking coffee specifically reduces the risk of antiestrogen-resistant estrogen-receptor (ER)-negative breast cancer.
Researchers from Sweden compared lifestyle factors and coffee consumption between women with breast cancer and age-matched women without. They found that coffee drinkers had a lower incidence of breast cancer than women who rarely drank coffee. However they also found that several lifestyle factors affected breast cancer rates, such as age at menopause, exercise, weight, education, and a family history of breast cancer. Once they had adjusted their data to account for these other factors they found that the protective effect of coffee on breast cancer was only measurable for ER-negative breast cancer.
The group from Karolinska Institutet explained that, "There is often conflicting information about the beneficial effects of coffee -- when we compared our results to that of a German study we discovered that their data showed the same trend, but the relationship was much weaker. We suggest that this may have something to do with the way the coffee was prepared, or the type of bean perred. It is unlikely that the protective effect is due to phytoestrogens present in coffee since there was no reduction in the incidence of ER-positive cancer in this study."
So while it is evident that coffee may have beneficial effects in protecting women from ER negative breast cancer the exact mechanism and compounds involved are not yet clear and not all types of coffee are the same.
New evidence that caffeine is a healthful antioxidant in coffee
Scientists are reporting an in-depth analysis of how the caffeine in coffee, tea, and other foods seems to protect against conditions such as Alzheimers disease and heart disease on the most fundamental levels. The report, which describes the chemistry behind caffeines antioxidant effects, appears in ACS The Journal of Physical Chemistry.
Annia Galano and Jorge Rafael León-Carmona describe evidence suggesting that coffee is one of the richest sources of healthful antioxidants in the average persons diet. Some of the newest research points to caffeine (also present in tea, cocoa, and other foods) as the source of powerful antioxidant effects that may help protect people from Alzheimers and other diseases. However, scientists know little about exactly how caffeine works in scavenging the so-called free radicals that have damaging effects in the body. And those few studies sometimes have reached contradictory conclusions.
In an effort to bolster scientific knowledge about caffeine, they present detailed theoretical calculations on caffeines interactions with free radicals. Their theoretical conclusions show "excellent" consistency with the results that other scientists have report from animal and other experiments, bolstering the likelihood that caffeine is, indeed, a source of healthful antioxidant activity in coffee.
Coffee protects against diabetes
Coffee, that morning elixir, may give us an early jump-start to the day, but numerous studies have shown that it also may be protective against type 2 diabetes. Yet no one has really understood why.
Now, researchers at UCLA have discovered a possible molecular mechanism behind coffees protective effect. A protein called sex hormone–binding globulin (SHBG) regulates the biological activity of the bodys sex hormones, testosterone and estrogen, which have long been thought to play a role in the development of type 2 diabetes. And coffee consumption, it turns out, increases plasma levels of SHBG.
Reporting with colleagues in the the journal Diabetes, first author Atsushi Goto, a UCLA doctoral student in epidemiology, and Dr. Simin Liu, a professor of epidemiology and medicine with joint appointments at the UCLA School of Public Health and the David Geffen School of Medicine at UCLA, show that women who drink at least four cups of coffee a day are less than half as likely to develop diabetes as non-coffee drinkers.
When the findings were adjusted for levels of SHBG, the researchers said, that protective effect disappeared.
The American Diabetes Association estimates that nearly 24 million children and adults in the U.S. — nearly 8 percent of the population — have diabetes. Type 2 diabetes is the most common form of the disease and accounts for about 90 to 95 percent of these cases.
Early studies have consistently shown that an "inverse association" exists between coffee consumption and risk for type 2 diabetes, Liu said. That is, the greater the consumption of coffee, the lesser the risk of diabetes. It was thought that coffee may improve the bodys tolerance to glucose by increasing metabolism or improving its tolerance to insulin.
"But exactly how is elusive," said Liu, "although we now know that this protein, SHBG, is critical as an early target for assessing the risk and prevention of the onset of diabetes."
Earlier work by Liu and his colleagues published in the New England Journal of Medicine had identified two mutations in the gene coding for SHBG and their effect on the risk of developing type 2 diabetes; one increases risk while the other decreases it, depending on the levels of SHBG in the blood.
A large body of clinical studies has implicated the important role of sex hormones in the development of type 2 diabetes, and its known that SHBG not only regulates the sex hormones that are biologically active but may also bind to receptors in a variety of cells, directly mediating the signaling of sex hormones.
"That genetic evidence significantly advanced the field," said Goto, "because it indicated that SHBG may indeed play a causal role in affecting risk for type 2 diabetes."
"It seems that SHBG in the blood does lect a genetic susceptibility to developing type 2 diabetes," Liu said. "But we now further show that this protein can be influenced by dietary factors such as coffee intake in affecting diabetes risk — the lower the levels of SHBG, the greater the risk beyond any known diabetes risk factors."
For the study, the researchers identified 359 new diabetes cases matched by age and race with 359 apparently healthy controls selected from among nearly 40,000 women enrolled in the Womens Health Study, a large-scale cardiovascular trial originally designed to evaluate the benefits and risks of low-dose aspirin and vitamin E in the primary prevention of cardiovascular disease and cancer.
They found that women who drank four cups of caffeinated coffee each day had significantly higher levels of SHBG than did non-drinkers and were 56 percent less likely to develop diabetes than were non-drinkers. And those who also carried the protective copy of the SHBG gene appeared to benefit the most from coffee consumption.
When the investigators controlled for blood SHBG levels, the decrease in risk associated with coffee consumption was not significant. This suggests that it is SHBG that mediates the decrease in risk of developing type 2 diabetes, Liu said.
And theres bad news for decaf lovers. "Consumption of decaffeinated coffee was not significantly associated with SHBG levels, nor diabetes risk," Goto said. "So you probably have to go for the octane!"
Coffee may protect against head and neck cancers
Data on the effects of coffee on cancer risk have been mixed. However, results of a recent study add to the brewing evidence that drinking coffee protects against cancer, this time against head and neck cancer.
Full study results are published online first in Cancer Epidemiology, Biomarkers & Prevention, a journal of the American Association for Cancer Research.
Using information from a pooled-analysis of nine studies collected by the International Head and Neck Cancer Epidemiology (INHANCE) consortium, participants who were regular coffee drinkers, that is, those who drank an estimated four or more cups a day, compared with those who were non-drinkers, had a 39 percent decreased risk of oral cavity and pharynx cancers combined.
Data on decaffeinated coffee was too sparse for detailed analysis, but indicated no increased risk. Tea intake was not associated with head and neck cancer risk.
The association is more reliable among those who are frequent, regular coffee drinkers, consuming more than four cups of coffee a day.
"Since coffee is so widely used and there is a relatively high incidence and low survival rate of these forms of cancers, our results have important public health implications that need to be further addressed," said lead researcher Mia Hashibe, Ph.D., assistant professor in the department of family and preventive medicine at the University of Utah, Salt Lake City, and a Huntsman Cancer Institute investigator.
"What makes our results so unique is that we had a very large sample size, and since we combined data across many studies, we had more statistical power to detect associations between cancer and coffee," she said.
At the AACR Frontiers in Cancer Prevention Research Conference last December, researchers from Harvard presented data that showed a strong inverse association between coffee consumption and the risk of lethal and advanced prostate cancers — men who drank the most coffee had a 60 percent lower risk of aggressive prostate cancer than men who did not drink any coffee.
More recently, results of another study published in the January issue of Cancer Epidemiology, Biomarkers & Prevention showed a decreased risk of gliomas, or brain tumors, associated with coffee. This association was found among those who drank five or more cups of coffee or tea a day, according the researchers from the Imperial College, London.
Cancer Epidemiology, Biomarkers & Prevention editorial board member Johanna W. Lampe, Ph.D., R.D., believes this current analysis by Hashibe and colleagues provides strong, additional evidence for an association between caffeinated coffee drinking and cancer risk.
"The fact that this was seen for oral and pharyngeal cancers, but not laryngeal cancers, provides some evidence as to a possible specificity of effect," said Lampe, who is a full member and associate division director in the division of public health sciences at Fred Hutchinson Cancer Research Center, Seattle., Wash.
"These findings provide further impetus to pursue research to understand the role of coffee in head and neck cancer prevention," she added. Lampe is not associated with this study.
Additional research is warranted to characterize the importance of timing and duration of exposure and possible mechanisms of action, according to Hashibe.
Coffee = Reduced Risk of Heart Rhythm Disturbances
Coffee drinkers may be less likely to be hospitalized for heart rhythm disturbances, according to a study by the Kaiser Permanente Division of Research in Oakland, Calif. The researchers note that the findings may be surprising because patients frequently report palpitations after drinking coffee.
While it has been established that very large doses of caffeine, the most active ingredient in coffee, can produce rhythm disturbances, there has been limited epidemiologic research about the caffeine doses people take. Previous data from a population study in Denmark compared heavy to light coffee drinkers with respect to risk of atrial fibrillation, the most common major rhythm disturbance, and found no statistically significant difference. This research presentation is believed to be the first large, multiethnic population study to look at all major types of heart rhythm disturbance, the researchers said.
The researchers followed 130,054 men and women and found that those who reported drinking four or more cups of coffee each day had an 18 percent lower risk of hospitalization for heart rhythm disturbances. Those who reported drinking one to three cups each day had a 7 percent reduction in risk, according to Arthur Klatsky, MD, the studys lead investigator and a senior consultant in cardiology at Kaiser Permanente Division of Research in Oakland, Calif.
"Coffee drinking is related to lower risk of hospitalization for rhythm problems, but the association does not prove cause and effect, or that coffee has a protective effect," Klasky said. Other explanations for the association might include other traits of coffee drinkers such as exercise or dietary habits. Additionally, some people with heart rhythm problems often are not hospitalized.
"However, these data might be reassuring to people who drink moderate amounts of coffee that their habit is not likely to cause a major rhythm disturbance," Klatsky said. While this report is not sufficient evidence to say that people should drink coffee to prevent rhythm problems, it supports the idea that people who are at risk for rhythm problems, or who have rhythm problems, do not necessarily need to abstain from coffee, emphasized Klatsky.
The long-term observational study involved 130,054 men and women, 18 to 90 years old, with the majority less than 50 years old. About 2 percent (3,317) were hospitalized for rhythm disturbances; 50 percent of those were for atrial fibrillation, the most common heart rhythm problem. The 18 percent reduction in risk was consistent among men and women, different ethnic groups, smokers and nonsmokers. It also was similar for various rhythm problems such as paroxysmal supraventricular tachycardia, atrial flutter, and atrial fibrillation.
Fourteen percent of the people in the study drank less than one cup of coffee a day; 42 percent drank one to three cups of coffee a day; and 17 percent reported drinking four cups or more each day. Only 27 percent of the people in the study were not coffee drinkers.
While emphasizing that these observational data do not establish causality and a protective mechanism is unclear, researchers speculate that moderate doses of caffeine may affect rhythm disturbances by antagonism of adenosine, a nucleoside compound widely distributed in the body. In the heart adenosine has several effects on conduction of electrical impulses, muscle cell energetics, and heart muscle cell recovery that might predispose to rhythm problems. Caffeine antagonizes adenosine effects by blocking its chemical sites of action.
The researchers examined hospitalization data by elapsed time after the initial examination. For hospitalization within 10 years, the reduction in hospitalizations for people who consumed four cups of coffee or more each day reached 28 percent.
The researchers also studied persons in the group with or without symptoms or history of heart and respiratory disease. For both groups, consuming four cups of coffee daily appeared to be associated with fewer hospitalizations for rhythm disturbances.
Coffee Consumption = Reduced Risk of Diabetes
Drinking more coffee (regular or decaffeinated) or tea appears to lower the risk of developing type 2 diabetes, according to an analysis of previous studies reported in the December 14/28 2009 issue of Archives of Internal Medicine, JAMA
By the year 2025, approximately 380 million individuals worldwide will be affected by type 2 diabetes (1).
Despite considerable research attention, the role of specific dietary and lifestyle factors remains uncertain, although obesity and physical inactivity have consistently been reported to raise the risk of diabetes mellitus. A previously published meta-analysis suggested drinking more coffee may be linked with a reduced risk, but the amount of available information has more than doubled since.
Rachel Huxley, D.Phil, of The George Institute for International Health, University of Sydney, Australia, and colleagues identified 18 studies involving 457,922 participants and assessing the association between coffee consumption and diabetes risk published between 1966 and 2009.
Six studies involving 225,516 individuals also included information about decaffeinated coffee, whereas seven studies with 286,701 participants reported on tea consumption.
When the authors combined and analyzed the data, they found that each additional cup of coffee consumed in a day was associated with a 7 percent reduction in the excess risk of diabetes.
Individuals who drank three to four cups per day had an approximately 25 percent lower risk than those who drank between zero and two cups per day.
In addition, in the studies that assessed decaffeinated coffee consumption, those who drank more than three to four cups per day had about a one-third lower risk of diabetes than those who drank none. Those who drank more than three to four cups of tea had a one-fifth lower risk than those who drank no tea.
That the apparent protective effect of tea and coffee consumption appears to be independent of a number of potential confounding variables raises the possibility of direct biological effects, the authors write. Because of the association between decaffeinated coffee and diabetes risk, the association is unlikely to be solely related to caffeine. Other compounds in coffee and tea including magnesium, antioxidants known as lignans or chlorogenic acids may be involved, the authors note.
If such beneficial effects were observed in interventional trials to be real, the implications for the millions of individuals who have diabetes mellitus, or who are at future risk of developing it, would be substantial, they conclude. For example, the identification of the active components of these beverages could open up therapeutic options for the primary prevention of diabetes mellitus. The findings also pose the question of whether patients most at risk for diabetes mellitus may in the future be advised to increase their consumption of tea and coffee in addition to increasing their levels of physical activity.
Spokesperson for the European Society of Cardiology, Professor Lars Rydén (Sweden), who is a diabetes specialist had the following advice: "This is a cautiously and caully conducted meta-analysis which means authors have caully conducted studies although each are too small to give an answer to the question although they indicate a positive correlation between the consumption of coffee and a decreasing occurrence of diabetes. So the principle is that if you drink coffee whether it is decaffeinated or not, you have less chance of developing diabetes. The data has been strengthened by bringing several studies together.
There are sometimes claims that coffee may do harm, that it may increase the propensity to Cardiovascular disease, but there is no evidence for this. The message is that people may drink coffee safely. Coffee from this point of view may actually be of benefit, as well as reducing the risk of getting diabetes – although the reduction is small (around 7%)."
However Prof Rydén warns that lifestyle changes far outweigh a regular coffee intake.
"Coffee helps, but other things are even more important. Those who are overweight should reduce their bodyweight by 5-10% - not too much - and include physical activity such as a brisk walk for 30 minutes a day. Then those people who are at risk of developing diabetes will reduce this risk by 40-50%.
It is interesting to consider why a beverage like coffee has a beneficial effect. It is obviously not the caffeine as decaffeinated coffee has the same efficiency as caffeinated coffee. Coffee may contain antioxidants but the studies have not measured the number of chemicals in the blood which is important."
Coffee Consumption Associated with Reduced Risk of Advanced Prostate Cancer
While it is too early for physicians to start advising their male patients to take up the habit of regular coffee drinking, data presented at the American Association for Cancer Research Frontiers in Cancer Prevention Research Conference revealed a strong inverse association between coffee consumption and the risk of lethal and advanced prostate cancers.
“Coffee has effects on insulin and glucose metabolism as well as sex hormone levels, all of which play a role in prostate cancer. It was plausible that there may be an association between coffee and prostate cancer,” said Kathryn M. Wilson, Ph.D., a postdoctoral fellow at the Channing Laboratory, Harvard Medical School and the Harvard School of Public Health.
In a prospective investigation, Wilson and colleagues found that men who drank the most coffee had a 60 percent lower risk of aggressive prostate cancer than men who did not drink any coffee. This is the first study of its kind to look at both overall risk of prostate cancer and risk of localized, advanced and lethal disease.
“Few studies have looked prospectively at this association, and none have looked at coffee and specific prostate cancer outcomes,” said Wilson. “We specifically looked at different types of prostate cancer, such as advanced vs. localized cancers or high-grade vs. low-grade cancers.”
Caffeine is actually not the key factor in this association, according to Wilson. The researchers are unsure which components of the beverage are most important, as coffee contains many biologically active compounds like antioxidants and minerals.
Using the Health Professionals’ Follow-Up Study, the researchers documented the regular and decaffeinated coffee intake of nearly 50,000 men every four years from 1986 to 2006; 4,975 of these men developed prostate cancer over that time. They also examined the cross-sectional association between coffee consumption and levels of circulating hormones in blood samples collected from a subset of men in the cohort.
“Very few lifestyle factors have been consistently associated with prostate cancer risk, especially with risk of aggressive disease, so it would be very exciting if this association is confirmed in other studies,” said Wilson. “Our results do suggest there is no reason to stop drinking coffee out of any concern about prostate cancer.”
This association might also help understand the biology of prostate cancer and possible chemoprevention measures.
Coffee W/O Milk Fights Bad Breath
We all know why Starbucks puts boxes of breath mints close to the cash register. Your morning latte can create a startling aroma in your mouth, strong enough to startle your co-workers too.
But intriguing research from Tel Aviv University by renowned breath specialist Prof. Mel Rosenberg of TAUs Sackler Faculty of Medicine finds that a coffee extract can inhibit the bacteria that lead to bad breath. laboratory tests have shown that the extract prevents malodorous bacteria from making their presence felt — or smelt.
"Everybody thinks that coffee causes bad breath," says Prof. Rosenberg, "and its often true, because coffee, which has a dehydrating effect in the mouth, becomes potent when mixed with milk, and can ferment into smelly substances."
But not always. "Contrary to our expectations, we found some components in coffee that actually inhibit bad breath," explains Prof. Rosenberg.
In the laboratory, the team monitored the bacterial odor production of coffee in saliva. In the study, three different brands of coffee were tested: the Israeli brand Elite coffee, Landwer Turkish coffee, and Tasters Choice. Prof. Rosenberg expected to demonstrate the malodor-causing effect of coffee in an in vitro saliva assay developed by Dr. Sarit Levitan in his laboratory. To his surprise, the extracts had the opposite effect.
"The lesson we learned here is one of humility," says Prof. Rosenberg. "We expected coffee would cause bad breath, but there is something inside this magic brew that has the opposite effect."
Prof. Rosenberg would love to isolate the bacterial-inhibiting molecule in order to reap the biggest anti-bacterial benefits from coffee. "Its not the raw extract we will use, he says, "but an active material within it." His latest discovery could be the foundation for an entirely class of mouthwash, breath mints and gum. Purified coffee extract can be added to a breath mint to stop bacteria from forming, stopping bad breath at its source, instead of masking the smell with a mint flavor.
Prof. Rosenberg is a successful scientist and inventor who has already developed a popular mouthwash sold widely in Europe, a pocket-based breath test, and an anti-odor chewing gum.
Caffeine reduces pain during exercise
Stopping to smell the coffee – and enjoy a cup of it – before your morning workout might do more than just get your juices flowing. It might keep you going for reasons you havent even considered.
As a former competitive cyclist, University of Illinois kinesiology and community health professor Robert Motl routinely met his teammates at a coffee shop to fuel up on caffeine prior to hitting the pavement on long-distance training rides.
"The notion was that caffeine was helping us train harder … to push ourselves a little harder," he said.
The cyclists didnt know why it helped, they just knew it was effective.
"I think intuitively a lot of people are taking caffeine before a workout and they dont realize the actual benefit theyre experiencing. That is, theyre experiencing less pain during the workout," Motl said.
He said its becoming increasingly common for athletes – before competing – to consume a variety of substances that include caffeine, motivated by "the notion that it will help you metabolize fat more readily."
"That research isnt actually very compelling," Motl said. "Whats going on in my mind is … people are doing it for that reason, but they actually take that substance that has caffeine and they can push themselves harder. It doesnt hurt as much."
The U. of I. professor has been investigating the relationship between caffeine and physical activity since taking a slight detour during his doctoral-student days, when his work initially was focused on exploring possible links between caffeine intake, spinal lexes and physical activity.
Seven years later, with several studies considering the relationship between physical activity and caffeine behind him, Motl has a much better understanding of why that cuppa Joe he used to consume before distance training and competing enhanced his cycling ability.
Early in his research, he became aware that "caffeine works on the adenosine neuromodulatory system in the brain and spinal cord, and this system is heavily involved in nociception and pain processing." Since Motl knew caffeine blocks adenosine from working, he speculated that it could reduce pain.
A number of studies by the U. of I. professor support that conclusion, including investigations considering such variables as exercise intensity, dose of caffeine, anxiety sensitivity and gender.
Motls latest published study on the effects of caffeine on pain during exercise appears in the April edition of the International Journal of Sport Nutrition and Exercise Metabolism.
"This study looks at the effects of caffeine on muscle pain during high-intensity exercise as a function of habitual caffeine use," he said. "No one has examined that before.
"What we saw is something we didnt expect: caffeine-naïve individuals and habitual users have the same amount of reduction in pain during exercise after caffeine (consumption)."
The studys 25 participants were fit, college-aged males divided into two distinct groups: subjects whose everyday caffeine consumption was extremely low to non-existent, and those with an average caffeine intake of about 400 milligrams a day, the equivalent of three to four cups of coffee.
After completing an initial exercise test in the lab on an ergometer, or stationary cycle, for determination of maximal oxygen consumption or aerobic power, subjects returned for two monitored high-intensity, 30-minute exercise sessions.
An hour prior to each session, cyclists – who had been instructed not to consume caffeine during the prior 24-hour period – were given a pill. On one occasion, it contained a dose of caffeine measuring 5 milligrams per kilogram of body weight (equivalent to two to three cups of coffee); the other time, they received a placebo.
During both exercise periods, subjects perceptions of quadriceps muscle pain was recorded at regular intervals, along with data on oxygen consumption, heart rate and work rate.
"Whats interesting," Motl said, "is that when we found that caffeine tolerance doesnt matter, we were perplexed at first. Then we looked at reviews of the literature relative to caffeine and tolerance effects across a variety of other stimuli. Sometimes you see them, sometimes you dont. That is, sometimes regular caffeine use is associated with a smaller response, whereas, other times, its not."
No ones been able to figure out the reason for the inconsistency, Motl said.
"Clearly, if you regularly consume caffeine, you have to have more to have that bigger, mental-energy effect. But the tolerance effect is not ubiquitous across all stimuli. Even brain metabolism doesnt show this tolerance-type effect. That is, with individuals who are habitual users versus non-habitual users, if you give them caffeine and do brain imaging, the activation is identical. Its really interesting why some processes show tolerance and others dont."
Regarding the outcome of the current research, he said, "it may just be that pain during exercise doesnt show tolerance effects to caffeine."
Motl said one of the next logical steps for his research team would be to conduct studies with rodents in order to better understand the biological mechanism for caffeine in reducing pain.
"If we can get at the biological mechanism, we can begin to understand why there may or may not be this kind of tolerance."
Motl said another research direction might be to determine caffeines effect on sport performance.
"Weve shown that caffeine reduces pain reliably, consistently during cycling, across different intensities, across different people, different characteristics. But does that reduction in pain translate into an improvement in sport performance?"
Meanwhile, the current research could prove encouraging for a range of people, including the average person who wants to become more physically active to realize the health benefits.
"One of the things that may be a practical application, is if you go to the gym and you exercise and it hurts, you may be prone to stop doing that because pain is an aversive stimulus that tells you to withdraw. So if we could give people a little caffeine and reduce the amount of pain theyre experiencing, maybe that would help them stick with that exercise.
"Maybe then theyll push a little harder as well … maybe get even better adaptations to the exercise."
Higher Coffee Consumption Associated with Lower Liver Cancer Risk
A large, prospective population-based study confirms an inverse relationship between coffee consumption and liver cancer risk. The study also found that higher levels of gamma-glutamyltransferase (GGT) in the blood were associated with an increased risk of developing the disease. These findings are published in the July issue of Hepatology, a journal published by John Wiley & Sons on behalf of the American Association for the Study of Liver Diseases (AASLD). The article and an accompanying editorial are also available online at Wiley Interscience (www.interscience.wiley.com).
Researchers led by Gang Hu at the University of Helsinki set out to examine the associations between coffee consumption and serum GGT with the risk of liver cancer in a large prospective cohort. Residents of Finland drink more coffee per capita than the Japanese, Americans, Italians, and other Europeans, so Hu and colleagues studied 60,323 Finnish participants ages 25 to 74 who were cancer-free at baseline. The Finns were included in seven independent cross-sectional population surveys conducted between 1972 and 2002 and followed up through June 2006.
The participants completed a mail-in questionnaire about their medical history, socioeconomic factors and dietary and lifestyle habits. For a subset of participants, clinical data was available, including serum levels of GGT. Data on subsequent cancer diagnoses was collected from the country-wide Finnish Cancer Registry.
Based on their answers to the question: “How many cups of coffee do you drink daily?” the participants were divided into five categories: 0-1 cup, 2-3 cups, 4-5 cups, 6-7 cups, and 8 or more cups per day. After a median follow-up period of 19.3 years, 128 participants were diagnosed with liver cancer.
The researchers noted a significant inverse association between coffee drinking and the risk of primary liver cancer. They found that the multivariable hazards ratio of liver cancer dropped for each group that drank more coffee. It fell from 1.00, to .66, to .44, to .38 to .32 respectively. “The biological mechanisms behind the association of coffee consumption with the risk of liver cancer are not known,” the authors point out.
They also found that high levels of serum GGT were associated with an increased risk of liver cancer. The hazard ratio of liver cancer for the highest vs. lowest quartile of serum GGT was 3.13. “Nevertheless,” they report, “the inverse association between coffee consumption and the risk of liver cancer was consistent in the subjects at any level of serum GGT.”
An accompanying editorial by Carlo La Vecchia of Milan says that Hu’s study solidly confirms the inverse relationship between coffee drinking and liver cancer risk, though we still don’t know if it is causal. “Furthermore, the study by Hu et al. provides original and important quantitative evidence that the levels of GGT are related to subsequent incidence of liver cancer, with an overall relative risk of 2.3,” he says.
La Vecchia notes, however, that, “It remains difficult, however, to translate the inverse relation between coffee drinking and liver cancer risk observed in epidemiological studies into potential implications for prevention of liver cancer by increasing coffee consumption.”
Coffee could protect against Alzheimers disease
A daily dose of caffeine blocks the disruptive effects of high cholesterol that scientists have linked to Alzheimers disease. A study in the open access publication, Journal of Neuroinflammation revealed that caffeine equivalent to just one cup of coffee a day could protect the blood-brain barrier (BBB) from damage that occurred with a high-fat diet.
The BBB protects the central nervous system from the rest of the bodys circulation, providing the brain with its own regulated microenvironment. Previous studies have shown that high levels of cholesterol break down the BBB which can then no longer protect the central nervous system from the damage caused by blood borne contamination. BBB leakage occurs in a variety of neurological disorders such as Alzheimers disease.
In this study, researchers from the University of North Dakota School of Medicine and Health Sciences gave rabbits 3 mg caffeine each day – the equivalent of a daily cup of coffee for an average-sized person. The rabbits were fed a cholesterol-enriched diet during this time.
After 12 weeks a number of laboratory tests showed that the BBB was significantly more intact in rabbits receiving a daily dose of caffeine.
“Caffeine appears to block several of the disruptive effects of cholesterol that make the blood-brain barrier leaky,” says Jonathan Geiger, University of North Dakota School of Medicine and Health Sciences. “High levels of cholesterol are a risk factor for Alzheimers disease, perhaps by compromising the protective nature of the blood-brain barrier. For the first time we have shown that chronic ingestion of caffeine protects the BBB from cholesterol-induced leakage.”
Caffeine appears to protect BBB breakdown by maintaining the expression levels of tight junction proteins. These proteins bind the cells of the BBB tightly to each other to stop unwanted molecules crossing into the central nervous system.
The findings confirm and extend results from other studies showing that caffeine intake protects against memory loss in aging and in Alzheimer’s disease.
“Caffeine is a safe and readily available drug and its ability to stabilise the blood-brain barrier means it could have an important part to play in therapies against neurological disorders,” says Geiger.
Coffee drinkers have slightly lower death rates than people who do not drink coffee
A study published in Annals of Internal Medicine has good news for coffee drinkers: Regular coffee drinking (up to 6 cups per day) is not associated with increased deaths in either men or women. In fact, both caffeinated and decaffeinated coffee consumption is associated with a somewhat smaller rate of death from heart disease.
"Coffee consumption has been linked to various beneficial and detrimental health effects, but data on its relation with death were lacking," says Esther Lopez-Garcia, PhD, the studys lead author. "Coffee consumption was not associated with a higher risk of mortality in middle-aged men and women. The possibility of a modest benefit of coffee consumption on heart disease, cancer, and other causes of death needs to be further investigated."
Women consuming two to three cups of caffeinated coffee per day had a 25 percent lower risk of death from heart disease during the follow-up period (which lasted from 1980 to 2004 and involved 84,214 women) as compared with non-consumers, and an 18 percent lower risk of death caused by something other than cancer or heart disease as compared with non-consumers during follow-up. For men, this level of consumption was associated with neither a higher nor a lower risk of death during the follow-up period (which lasted from 1986 to 2004 and involved 41,736 men).
The researchers analyzed data of 84,214 women who had participated in the Nurses Health Study and 41,736 men who had participated in the Health Professionals Follow-up Study. To be in the current study, participants had to have been free of cancer and heart disease at the start of those larger studies.
The study participants completed questionnaires every two to four years that included questions about how frequently they drank coffee, other diet habits, smoking, and health conditions. The researchers then compared the frequency of death from any cause, death due to heart disease, and death due to cancer among people with different coffee-drinking habits.
Among women, 2,368 deaths were due to heart disease, 5,011 were due to cancer, and 3,716 were due to another cause. Among men, 2,049 deaths were due to heart disease, 2,491 were due to cancer, and 2,348 were due to another cause.
While accounting for other risk factors, such as body size, smoking, diet, and specific diseases, the researchers found that people who drank more coffee were less likely to die during the follow-up period. This was mainly because of lower risk for heart disease deaths among coffee drinkers.
The researchers found no association between coffee drinking and cancer deaths. These relationships did not seem to be related to caffeine because people who drank decaffeinated coffee also had lower death rates than people who did not drink coffee.
The editors of Annals of Internal Medicine caution that the design of the study does not make it certain that coffee decreases the chances of dying sooner than expected. Something else about coffee drinkers might be protecting them. And some measurement error in the assessment of coffee consumption is inevitable because estimated consumption came from self-reports.
In women, caffeine may protect memory
Caffeine may help older women protect their thinking skills, according to a study published in the August 7, 2007, issue of Neurology, the medical journal of the American Academy of Neurology.
The study found that women age 65 and older who drank more than three cups of coffee (or the equivalent in tea) per day had less decline over time on tests of memory than women who drank one cup or less of coffee or tea per day. The results held up even after researchers adjusted for other factors that could affect memory abilities, such as age, education, disability, depression, high blood pressure, medications, cardiovascular disease, and other chronic illnesses.
“Caffeine is a psychostimulant which appears to reduce cognitive decline in women,” said study author Karen Ritchie,. “While we have some ideas as to how this works biologically, we need to have a better understanding of how caffeine affects the brain before we can start promoting caffeine intake as a way to reduce cognitive decline. But the results are interesting – caffeine use is already widespread and it has fewer side effects than other treatments for cognitive decline, and it requires a relatively small amount for a beneficial effect.”
The study involved 7,000 people whose cognitive abilities and caffeine consumption were evaluated over four years. Compared to women who drank one cup or less of coffee per day, those who drank over three cups were less likely to show as much decline in memory. Moreover, the benefits increased with age – coffee drinkers being 30 percent less likely to have memory decline at age 65 and rising to 70 percent less likely over age 80.
Caffeine consumers did not seem to have lower rates of dementia. “We really need a longer study to look at whether caffeine prevents dementia; it might be that caffeine could slow the dementia process rather than preventing it,” said Ritchie.
Ritchie said researchers aren’t sure why caffeine didn’t show the same result in men. “Women may be more sensitive to the effects of caffeine,” she said. “Their bodies may react differently to the stimulant, or they may metabolize caffeine differently.”
Caffeine may prevent heart disease death in elderly
Habitual intake of caffeinated beverages provides protection against heart disease mortality in the elderly, say researchers at SUNY Downstate Medical Center and Brooklyn College._
Using data from the first federal National Health and Nutrition Examination Survey Epidemiologic Follow-up Study, the researchers found that survey participants 65 or more years old with higher caffeinated beverage intake exhibited lower relative risk of coronary vascular disease and heart mortality than did participants with lower caffeinated beverage intake.__
John Kassotis, MD, associate professor of medicine at SUNY Downstate, said, "The protection against death from heart disease in the elderly afforded by caffeine is likely due to caffeines enhancement of blood pressure."_
The protective effect also was found to be dose-responsive: the higher the caffeine intake the stronger the protection. The protective effect was found only in participants who were not severely hypertensive. No significant protective effect was in patients below the age of 65.
Coffee consumption may lower blood uric acid levels
High uric acid levels in the blood are a precursor of gout, the most common inflammatory arthritis in adult men. It is believed that coffee and tea consumption may affect uric acid levels but only one study has been conducted to date. A large-scale study published in the June 2007 issue of Arthritis Care & Research (http://www.interscience.wiley.com/journal/arthritiscare) examined the relationship between coffee, tea, caffeine intake, and uric acid levels and found that coffee consumption is associated with lower uric acid levels but that this appears to be due to components other than caffeine.
Coffee is one of the most widely consumed beverages in the world; more than 50 percent of Americans drink it at the average rate of 2 cups per day. Because of this widespread consumption, its potential effects have important implications for public and individual health. Led by Hyon K. Choi, of the University of British Columbia in Vancouver, Canada, the current study was based on the U.S. Third National Health and Nutrition Examination Survey, conducted between 1988 and 1994. It included over 14,000 men and women at least 20 years old who consented to a medical exam in which blood and urine specimens were obtained. Coffee and tea consumption were determined based on responses to a food questionnaire that assessed intake over the previous month. Researchers estimated the amount of caffeine per cup of coffee or tea using data from the U.S. Department of Agriculture.
The results showed that levels of uric acid in the blood significantly decreased with increasing coffee intake, but not with tea intake. In addition, there was no association between total caffeine intake from beverages and uric acid levels. These results were similar to those found in the only previous study on the topic, which was conducted in Japan. Interestingly, there was an association between decaffeinated coffee consumption and uric acid levels. "These findings suggest that components of coffee other than caffeine contribute to the observed inverse association between coffee intake and uric acid levels," the researchers state.
A recent study found that coffee was associated lower C peptide levels (a marker of insulin levels). The researchers in the current study suggest that because there is a strong relationship between insulin resistance and elevated uric acid levels, the decreased insulin levels associated with coffee consumption may lead to lower uric acid levels. Coffee is also a major source of chlorogenic acid, a strong antioxidant, which may improve insulin sensitivity. Chlorogenic acid also helps inhibit glucose absorption in the intestine; in another study decaffeinated coffee seemed to delay intestinal absorption of glucose and increase concentrations of glucagon-like peptide 1, which is well known for its beneficial effects on insulin secretion and action. The researchers note further that their results could be due to an effect of non-caffeine components found in coffee, which would also explain why coffee affected uric acid levels but tea did not.
To examine how coffee consumption might aggravate or protect against this common and excruciatingly painful condition, researchers at the Arthritis Research Centre of Canada, University of British Columbia in Canada, Brigham and Women’s Hospital, Harvard Medical School, and Harvard School of Public Health in Boston conducted a prospective study on 45,869 men over age 40 with no history of gout at baseline. Over 12 years of follow-up, Hyon K. Choi, MD, DrPH, and his associates evaluated the relationship between the intake of coffee and the incidence of gout in this high risk population. Their findings, featured in the June 2007 issue of Arthritis & Rheumatism (http://www.interscience.wiley.com/journal/arthritis), provide compelling evidence that drinking 4 or more cups of coffee a day dramatically reduces the risk of gout for men.
Subjects were drawn from an ongoing study of some 50,000 male health professionals, 91 percent white, who were between 40 and 75 years of age in 1986 when the project was initiated. To assess coffee and total caffeine intake, Dr. Choi and his team used a food-frequency questionnaire, updated every 4 years. Participants chose from 9 frequency responses – ranging from never to 2 to 4 cups per week to 6 or more per day – to record their average consumption of coffee, decaffeinated coffee, tea, and other caffeine-containing comestibles, such as cola and chocolate.
Through another questionnaire, the researchers documented 757 newly diagnosed cases meeting the American College of Rheumatology criteria for gout during the follow-up period. Then, they determined the relative risk of incident gout for long-term coffee drinkers divided into 4 groups – less than 1 cup per day, 1 to 3 cups per day, 4 to 5 cups per day, and 6 or more cups per day – as well as for regular drinkers of decaffeinated coffee, tea, and other caffeinated beverages. They also evaluated the impact of other risk factors for gout – body mass index, history of hypertension, alcohol use, and a diet high in red meat and high-fat dairy foods among them – on the association between coffee consumption and gout among the study participants.
Most significantly, the data revealed that the risk for developing gout decreased with increasing coffee consumption. The risk of gout was 40 percent lower for men who drank 4 to 5 cups a day and 59 percent lower for men who drank 6 or more cups a day than for men who never drank coffee. There was also a modest inverse association with decaffeinated coffee consumption. These findings were independent of all other risk factors for gout. Tea drinking and total caffeine intake were both shown to have no effect on the incidence of gout among the subjects. On the mechanism of these findings, Dr. Choi speculates that components of coffee other than caffeine may be responsible for the beverage’s gout-prevention benefits. Among the possibilities, coffee contains the phenol chlorogenic acid, a strong antioxidant.
While not prescribing 4 or more cups a day, this study can help individuals make an informed choice regarding coffee consumption. "Our findings are most directly generalizable to men age 40 years and older, the most gout-prevalent population, with no history of gout," Dr. Choi notes. "Given the potential influence of female hormones on the risk of gout in women and an increased role of dietary impact on uric acid levels among patients with existing gout, prospective studies of these populations would be valuable."
Moderate coffee drinking reduces many risks
Although the American Society for Nutrition’s popular “controversy session” at Experimental Biology 2007 focuses on the health effects of coffee drinking, panel chair Dr. James Coughlin, a toxicology/safety consultant at Coughlin & Associates, says that recent advances in epidemiologic and experimental knowledge have transformed many of the negative health myths about coffee drinking into validated health benefits.
Indeed, panel co-chair Dan Steffen, who follows coffee and health issues in the Scientific and Regulatory Affairs group of Kraft Foods, note that the “controversy” is often to educate a wider audience about this transformation in understanding.
Coffee is among the most widely consumed beverages in the world, and Dr. Coughlin says that the preponderance of scientific evidence - some by the panelists - suggests that moderate coffee consumption (3-5 cups per day) may be associated with reduced risk of certain disease conditions, such as Parkinson’s disease. Some research in neuropharamacology suggests that one cup of coffee can halve the risk of Parkinson’s disease. Other studies have found it reduces the risk of Alzheimers disease, kidney stones, gallstones, depression and even suicide.
Dr. Coughlin and two distinguished researchers discussed some of the benefits - and a couple of the remaining increased risk factors (possible increase in blood pressure and plasma homocysteine) - on April 30 at the Experimental Biology meeting in Washington, DC.
Dr. Rob van Dam, an epidemiologist at the Harvard School of Public Health and the Harvard Medical School, studies the link between diet and the development of type 2 diabetes. Worldwide, an estimated 171 million persons have diabetes, mostly type 2 diabetes, and an alarming increase to 366 million persons is expected for the year 2030. While increased physical activity and restriction of energy intake can substantially reduce risk of type 2 diabetes, he believes insight into the role of other lifestyle factors may contribute to additional prevention strategies for type 2 diabetes.
In recent epidemiological studies in the U.S., Europe and Japan, persons who were heavy coffee consumers had a lower risk of type 2 diabetes than persons who consumed little coffee. Interestingly, he says, associations were similar for caffeinated and decaffeinated coffee, suggesting that coffee components other than caffeine may be beneficial for glucose metabolism.
Coffee contains hundreds of components including substantial amounts of chlorogenic acid, caffeine, magnesium, potassium, vitamin B3, trigonelline, and lignans. Limited evidence suggests that coffee may improve glucose metabolism by reducing the rate of intestinal glucose absorption and by stimulating the secretion of the gut hormone glucagon-like peptide-1 (GLP-1) that is beneficial for the secretion of insulin. However, most mechanistic research on coffee and glucose metabolism has been done in animals and in lab tubes and theore metabolic studies in humans are currently being conducted. Further research may lead to the development or selection of coffee types with improved health effects.
Dr. Lenore Arab, a nutritional epidemiologist in the David Geffen School of Medicine at UCLA, notes that the first coffee controversy dates back 430 years when in 1570 some monks petitioned the pope to condemn this drink, so popular among Muslims. Pope Clement VIII, liking how it kept the monks from falling sleep during mass, purportedly blessed it instead. The rest, including the United States’ wholesale conversion to coffee following the Boston Tea Party, is history.
In reviewing the latest epidemiologic literature on cancers and coffee, Dr. Arab has found there to be close to 400 studies of the associations between coffee consumption and cancers various at various sites. The earlier controversy with regard to colon cancer was based on flawed analyses, she says. More thorough analyses and the accumulation of evidence suggest no negative effect on the incidence of colon cancer, and possible protective effects for adenomas of the colon as well as for rectal cancer and liver cancer. Mechanisms which might contribute to a possible anticarcinogenic effect include reduction in cholesterol, bile acid and neutral sterol secretion in the colon, increased colonic motility and reduced exposure of epithelium to carcinogens, the ability of diterpenes to reduce genotoxicity of carcinogens, and lower DNA adduct formation, and the ability of caffeic acid and chlorogenic acid to decreased DNA methylation. In other cancers - breast, ovarian, and prostate - the evidence is not suggestive of either risk or protection. There are two areas, says Dr. Arab, in which there is some evidence of increased risk: leukemia and stomach cancer. The evidence for the former is intriguing, for the latter insubstantial. She concludes that a systematic review of the newer data for liver, rectal, stomach cancer and for childhood leukemia is due.
Study finds that caffeine cuts post-workout pain by nearly 50 percent
Although it’s too soon to recommend dropping by Starbucks before hitting the gym, a study suggests that caffeine can help reduce the post-workout soreness that discourages some people from exercising.
In a study published in the February 2007 issue of The Journal of Pain, a team of University of Georgia researchers finds that moderate doses of caffeine, roughly equivalent to two cups of coffee, cut post-workout muscle pain by up to 48 percent in a small sample of volunteers.
Lead author Victor Maridakis, a researcher in the department of kinesiology at the UGA College of Education, said the findings may be particularly relevant to people to exercise, since they tend to experience the most soreness.
“If you can use caffeine to reduce the pain, it may make it easier to transition from that first week into a much longer exercise program,” he said.
Maridakis and his colleagues studied nine female college students who were not regular caffeine users and did not engage in regular resistance training. One and two days after an exercise session that caused moderate muscle soreness, the volunteers took either caffeine or a placebo and performed two different quadriceps (thigh) exercises, one designed to produce a maximal force, the other designed to generate a sub-maximal force. Those that consumed caffeine one-hour before the maximum force test had a 48 percent reduction in pain compared to the placebo group, while those that took caffeine before the sub-maximal test reported a 26 percent reduction in pain.
Caffeine has long been known to increase alertness and endurance, and a 2003 study led by UGA professor Patrick O’Connor found that caffeine reduces thigh pain during moderate-intensity cycling. O’Connor, who along with professors Kevin McCully and the late Gary Dudley co-authored the current study, explained that caffeine likely works by blocking the body’s receptors for adenosine, a chemical released in response to inflammation.
Despite the positive findings in the study, the researchers say there are some caveats. First, the results may not be applicable to regular caffeine users, since they may be less sensitive to caffeine’s effect. The researchers chose to study women to get a definitive answer in at least one sex, but men may respond differently to caffeine. And the small sample size of nine volunteers means that the study will have to be replicated with a larger study.
O’Connor said that despite these limitations, caffeine appears to be more effective in relieving post-workout muscle pain than several commonly used drugs. Previous studies have found that the pain reliever naproxen (the active ingredient in Aleve) produced a 30 percent reduction in soreness. Aspirin produced a 25 percent reduction, and ibuprofen has produced inconsistent results.
“A lot of times what people use for muscle pain is aspirin or ibuprofen, but caffeine seems to work better than those drugs, at least among women whose daily caffeine consumption is low,” O’Connor said.
Still, the researchers recommend that people use caution when using caffeine before a workout. For some people, too much caffeine can produce side effects such as jitteriness, heart palpitations and sleep disturbances.
“It can reduce pain,” Maridakis said, “but you have to apply some common sense and not go overboard.”
Update:
Coffee consumption reduces risk of liver cancer
Coffee consumption reduces risk of hepatocellular carcinoma (HCC), the most common type of liver cancer, by about 40 percent, according to an up-to-date meta-analysis published in Clinical Gastroenterology and Hepatology, the official clinical practice journal of the American Gastroenterological Association. Further, some data indicate that three cups of coffee per day reduce liver cancer risk by more than 50 percent.
Coffee may help lower stroke risk
Green tea and coffee may help lower your risk of having a stroke, especially when both are a regular part of your diet, according to research published in Stroke: Journal of the American Heart Association.
People who drank at least one cup of coffee daily had about a 20 percent lower risk of stroke compared to those who rarely drank it.
As coffee drinking increased, the risk of death decreased
A large study of nearly half a million older adults followed for about 12 years revealed a clear trend: as coffee drinking increased, the risk of death decreased. Study author Neal Freedman, PhD, MPH, National Cancer Institute, discusses the significance of these findings and the potential links between coffee drinking, caffeine consumption, and various specific causes of disease in an interview in Journal of Caffeine Research, a peer-reviewed journal from Mary Ann Liebert, Inc., publishers. The article is available on the Journal of Caffeine Research website.
"Epidemiology of Caffeine Consumption and Association of Coffee Drinking with Total and Cause-specific Mortality" presents an in-depth interview exploring the many factors that could contribute to the association between coffee, disease, and mortality.
Four or more cups of coffee a day may keep prostate cancer recurrence and progression away
Consuming Coffee = Lower Risk of Liver Disease
Coffee may help prevent breast cancer returning
Caffeinated coffee may reduce the risk of oral cancers
Moderate coffee consumption may reduce risk of diabetes by up to 25 percent
Original report:
Coffee consumption lowers risk of most common form of skin cancer
Increasing the number of cups of caffeinated coffee you drink could lower your risk of developing the most common form of skin cancer, basal cell carcinoma, according to a study published in Cancer Research, a journal of the American Association for Cancer Research.
"Our data indicate that the more caffeinated coffee you consume, the lower your risk of developing basal cell carcinoma," said Jiali Han, Ph.D., associate professor at Brigham and Womens Hospital, Harvard Medical School in Boston and Harvard School of Public Health.
"I would not recommend increasing your coffee intake based on these data alone," said Han. "However, our results add basal cell carcinoma to a list of conditions for which risk is decreased with increasing coffee consumption. This list includes conditions with serious negative health consequences such as type 2 diabetes and Parkinsons disease."
Basal cell carcinoma is the form of skin cancer most commonly diagnosed in the United States. Even though it is slow-growing, it causes considerable morbidity and places a burden on health care systems.
"Given the large number of newly diagnosed cases, daily dietary changes having any protective effect may have an impact on public health," said Han.
Han and his colleagues generated their results by conducting a prospective analysis of data from the Nurses Health Study, a large and long-running study to aid in the investigation of factors influencing womens health, and the Health Professionals Follow-up Study, an analogous study for men.
Of the 112,897 participants included in the analyses, 22,786 developed basal cell carcinoma during the more than 20 years of follow-up in the two studies. An inverse association was observed between all coffee consumption and risk of basal cell carcinoma. Similarly, an inverse association was seen between intake of caffeine from all dietary sources (coffee, tea, cola and chocolate) and risk of basal cell carcinoma. However, consumption of decaffeinated coffee was not associated with a decreased risk of basal cell carcinoma.
Moderate coffee consumption offers protection against heart failure
While current American Heart Association heart failure prevention guidelines warn against habitual coffee consumption, some studies propose a protective benefit, and still others find no association at all. Amidst this conflicting information, research from Beth Israel Deaconess Medical Center attempts to shift the conversation from a definitive yes or no, to a question of how much.
"Our results did show a possible benefit, but like with so many other things we consume, it really depends on how much coffee you drink," says lead author Elizabeth Mostofsky, MPH, ScD, a post-doctoral fellow in the cardiovascular epidemiological unit at BIDMC. "And compared with no consumption, the strongest protection we observed was at about four European, or two eight-ounce American, servings of coffee per day."
The study published June 26 online in the Journal Circulation: Heart Failure, found that these moderate coffee drinkers were at 11 percent lower risk of heart failure.
Data was analyzed from five previous studies – four conducted in Sweden, one in Finland – that examined the association between coffee consumption and heart failure. The self-reported data came from 140,220 participants and involved 6,522 heart failure events.
In a summary of the published literature, the authors found a "statistically significant J-shaped relationship" between habitual coffee consumption and heart failure, where protective benefits begin to increase with consumption maxing out at two eight-ounce American servings a day. Protection slowly decreases the more coffee is consumed until at five cups, there is no benefit and at more than five cups a day, there may be potential for harm.
Its unclear why moderate coffee consumption provides protection from heart failure, but the researchers say part of the answer may lie in the intersection between regular coffee drinking and two of the strongest risk factors for heart failure – diabetes and elevated blood pressure.
"There is a good deal of research showing that drinking coffee lowers the risk for type 2 diabetes, says senior author Murray Mittleman, MD, DrPH, a physician in the Cardiovascular Institute at Beth Israel Deaconess Medical Center, an Associate Professor of Medicine at Harvard Medical School and director of BIDMCs cardiovascular epidemiological research program. "It stands to reason that if you lower the risk of diabetes, you also lower the risk of heart failure."
There may also be a blood pressure benefit. Studies have consistently shown that light coffee and caffeine consumption are known to raise blood pressure. "But at that moderate range of consumption, people tend to develop a tolerance where drinking coffee does not pose a risk and may even be protective against elevated blood pressure," says Mittleman.
This study was not able to assess the strength of the coffee, nor did it look at caffeinated versus non-caffeinated coffee.
"There is clearly more research to be done," says Mostofsky. "But in the short run, this data may warrant a change to the guidelines to lect that coffee consumption, in moderation, may provide some protection from heart failure."
High blood caffeine levels linked to avoidance of Alzheimers disease
Those cups of coffee that you drink every day to keep alert appear to have an extra perk – especially if youre an older adult. A recent study monitoring the memory and thinking processes of people older than 65 found that all those with higher blood caffeine levels avoided the onset of Alzheimers disease in the two-to-four years of study follow-up. Moreover, coffee appeared to be the major or only source of caffeine for these individuals.
Researchers from the University of South Florida (www.usf.edu) and the University of Miami (www.miami.edu)say the case control study provides the first direct evidence that caffeine/coffee intake is associated with a reduced risk of dementia or delayed onset. Their findings will appear in the online version of an article to be published June 5 in the Journal of Alzheimers Disease, published by IOS Press (http://health.usf.edu/nocms/publicaffairs/now/pdfs/JAD111781.pdf). The collaborative study involved 124 people, ages 65 to 88, in Tampa and Miami.
"These intriguing results suggest that older adults with mild memory impairment who drink moderate levels of coffee -- about 3 cups a day -- will not convert to Alzheimers disease -- or at least will experience a substantial delay before converting to Alzheimers," said study lead author Dr. Chuanhai Cao, a neuroscientist at the USF College of Pharmacy (http://health.usf.edu/nocms/pharmacy/) and the USF Health Byrd Alzheimers Institute (http://health.usf.edu/nocms/byrd/). "The results from this study, along with our earlier studies in Alzheimers mice, are very consistent in indicating that moderate daily caffeine/coffee intake throughout adulthood should appreciably protect against Alzheimers disease later in life."
The study shows this protection probably occurs even in older people with early signs of the disease, called mild cognitive impairment, or MCI. Patients with MCI already experience some short-term memory loss and initial Alzheimers pathology in their brains. Each year, about 15 percent of MCI patients progress to full-blown Alzheimers disease. The researchers focused on study participants with MCI, because many were destined to develop Alzheimers within a few years.
Blood caffeine levels at the studys onset were substantially lower (51 percent less) in participants diagnosed with MCI who progressed to dementia during the two-to-four year follow-up than in those whose mild cognitive impairment remained stable over the same period.
No one with MCI who later developed Alzheimers had initial blood caffeine levels above a critical level of 1200 ng/ml – equivalent to drinking several cups of coffee a few hours before the blood sample was drawn. In contrast, many with stable MCI had blood caffeine levels higher than this critical level.
"We found that 100 percent of the MCI patients with plasma caffeine levels above the critical level experienced no conversion to Alzheimers disease during the two-to-four year follow-up period," said study co-author Dr. Gary Arendash.
The researchers believe higher blood caffeine levels indicate habitually higher caffeine intake, most probably through coffee. Caffeinated coffee appeared to be the main, if not exclusive, source of caffeine in the memory-protected MCI patients, because they had the same profile of blood immune markers as Alzheimers mice given caffeinated coffee. Alzheimers mice given caffeine alone or decaffeinated coffee had a very different immune marker profile.
Since 2006, USFs Dr. Cao and Dr. Arendash have published several studies investigating the effects of caffeine/coffee administered to Alzheimers mice. Most recently, they reported that caffeine interacts with a yet unidentified component of coffee to boost blood levels of a critical growth factor that seems to fight off the Alzheimers disease process.
"We are not saying that moderate coffee consumption will completely protect people from Alzheimers disease," Dr. Cao cautioned. "However, we firmly believe that moderate coffee consumption can appreciably reduce your risk of Alzheimers or delay its onset."
Alzheimers pathology is a process in which plaques and tangles accumulate in the brain, killing nerve cells, destroying neural connections, and ultimately leading to progressive and irreversible memory loss. Since the neurodegenerative disease starts one or two decades before cognitive decline becomes apparent, the study authors point out, any intervention to cut the risk of Alzheimers should ideally begin that far in advance of symptoms.
"Moderate daily consumption of caffeinated coffee appears to be the best dietary option for long-term protection against Alzheimers memory loss," Dr. Arendash said. "Coffee is inexpensive, readily available, easily gets into the brain, and has few side-effects for most of us. Moreover, our studies show that caffeine and coffee appear to directly attack the Alzheimers disease process."
In addition to Alzheimers disease, moderate caffeine/coffee intake appears to reduce the risk of several other diseases of aging, including Parkinsons disease, stroke, Type II diabetes, and breast cancer. However, supporting studies for these benefits have all been observational (uncontrolled), and controlled clinical trials are needed to definitively demonstrate therapeutic value.
A study tracking the health and coffee consumption of more than 400,000 older adults for 13 years, and published earlier this year in the New England Journal of Medicine, found that coffee drinkers reduced their risk of dying from heart disease, lung disease, pneumonia, stroke, diabetes, infections, and even injuries and accidents.
With new Alzheimers diagnostic guidelines encompassing the full continuum of the disease, approximately 10 million Americans now fall within one of three developmental stages of Alzheimers disease -- Alzheimers disease brain pathology only, MCI, or diagnosed Alzheimers disease. That number is expected to climb even higher as the baby-boomer generation continues to enter older age, unless an effective and proven preventive measure is identified.
"If we could conduct a large cohort study to look into the mechanisms of how and why coffee and caffeine can delay or prevent Alzheimers disease, it might result in billions of dollars in savings each year in addition to improved quality of life," Dr. Cao said.
Coffee drinkers have lower risk of death
Older adults who drank coffee -- caffeinated or decaffeinated -- had a lower risk of death overall than others who did not drink coffee, according a study by researchers from the National Cancer Institute (NCI), part of the National Institutes of Health, and AARP.
Coffee drinkers were less likely to die from heart disease, respiratory disease, stroke, injuries and accidents, diabetes, and infections, although the association was not seen for cancer. These results from a large study of older adults were observed after adjustment for the effects of other risk factors on mortality, such as smoking and alcohol consumption. Researchers caution, however, that they can’t be sure whether these associations mean that drinking coffee actually makes people live longer. The results of the study were published in the May 17, 2012, edition of the New England Journal of Medicine.
Neal Freedman, Ph.D., Division of Cancer Epidemiology and Genetics, NCI, and his colleagues examined the association between coffee drinking and risk of death in 400,000 U.S. men and women ages 50 to 71 who participated in the NIH-AARP Diet and Health Study. Information about coffee intake was collected once by questionnaire at study entry in 1995-1996. The participants were followed until the date they died or Dec. 31, 2008, whichever came first.
The researchers found that the association between coffee and reduction in risk of death increased with the amount of coffee consumed. Relative to men and women who did not drink coffee, those who consumed three or more cups of coffee per day had approximately a 10 percent lower risk of death. Coffee drinking was not associated with cancer mortality among women, but there was a slight and only marginally statistically significant association of heavier coffee intake with increased risk of cancer death among men.
“Coffee is one of the most widely consumed beverages in America, but the association between coffee consumption and risk of death has been unclear. We found coffee consumption to be associated with lower risk of death overall, and of death from a number of different causes,’’ said Freedman. “Although we cannot infer a causal relationship between coffee drinking and lower risk of death, we believe these results do provide some reassurance that coffee drinking does not adversely affect health.”
The investigators caution that coffee intake was assessed by self-report at a single time point and theore might not lect long-term patterns of intake. Also, information was not available on how the coffee was prepared (espresso, boiled, filtered, etc.); the researchers consider it possible that preparation methods may affect the levels of any protective components in coffee.
“The mechanism by which coffee protects against risk of death -- if indeed the finding lects a causal relationship -- is not clear, because coffee contains more than 1,000 compounds that might potentially affect health,’’ said Freedman. ``The most studied compound is caffeine, although our findings were similar in those who reported the majority of their coffee intake to be caffeinated or decaffeinated.”
Caffeine consumption = decreased risk of liver disease
Caffeine consumption has long been associated with decreased risk of liver disease and reduced fibrosis in patients with chronic liver disease. Now, newly published research confirms that coffee caffeine consumption reduces the risk of advanced fibrosis in those with nonalcoholic fatty liver disease (NAFLD). Findings published in the February, 2012 issue of Hepatology, a journal of the American Association for the Study of Liver Diseases, show that increased coffee intake, specifically among patients with nonalcoholic steatohepatitis (NASH), decreases risk of hepatic fibrosis.
The steady increase in rates of diabetes, obesity, and metabolic syndrome over the past 20 years has given rise to greater prevalence of NAFLD. In fact, experts now believe NAFLD is the leading cause of chronic liver disease in the U.S., surpassing both hepatitis B and C. The majority of patients will have isolated fatty liver which has a very low likelihood of developing progressive liver disease. However, a subset of patients will have NASH, which is characterized by inflammation of the liver, destruction of liver cells, and possibly scarring of the liver. Progression to cirrhosis (advanced scarring of the liver) may occur in about 10-11% of NASH patients over a 15 year period, although this is highly variable.
To enhance understanding of the correlation between coffee consumption and the prevalence and severity of NAFLD, a team led by Dr. Stephen Harrison, Lieutenant Colonel, U.S. Army at Brooke Army Medical Center in Fort Sam Houston, Texas surveyed participants from a previous NAFLD study as well as NASH patients treated at the centers hepatology clinic. The 306 participants were asked about caffeine coffee consumption and categorized into four groups: patients with no sign of fibrosis on ultrasound (control), steatosis, NASH stage 0-1, and NASH stage 2-4.
Researchers found that the average milligrams in total caffeine consumption per day in the control, steatosis, Nash 0-1, and Nash 2-4 groups was 307, 229, 351 and 252; average milligrams of coffee intake per day was 228, 160, 255, and 152, respectively. There was a significant difference in caffeine consumption between patients in the steatosis group compared to those with NASH stage 0-1. Coffee consumption was significantly greater for patients with NASH stage 0-1, with 58% of caffeine intake from regular coffee, than with NASH stage 2-4 patients at only 36% of caffeine consumption from regular coffee.
Multiple analyses showed a negative correlation between coffee consumption and risk of hepatic fibrosis. "Our study is the first to demonstrate a histopatholgic relationship between fatty liver disease and estimated coffee intake," concludes Dr. Harrison. "Patients with NASH may benefit from moderate coffee consumption that decreases risk of advanced fibrosis. Further prospective research should examine the amount of coffee intake on clinical outcomes."
Coffee may protect against endometrial cancer
Long-term coffee consumption may be associated with a reduced risk for endometrial cancer, according to a recent study in Cancer Epidemiology, Biomarkers & Prevention, a journal of the American Association for Cancer Research.
Edward Giovannucci, M.D., Sc.D., professor of nutrition and epidemiology at the Harvard School of Public Health, said coffee is emerging as a protective agent in cancers that are linked to obesity, estrogen and insulin.
"Coffee has already been shown to be protective against diabetes due to its effect on insulin," said Giovannucci, a senior researcher on the study. "So we hypothesized that wed see a reduction in some cancers as well."
Giovannucci, along with Youjin Je, a doctoral candidate in his lab, and colleagues observed cumulative coffee intake in relation to endometrial cancer in 67,470 women who enrolled in the Nurses Health Study.
During the course of 26 years of follow-up, researchers documented 672 cases of endometrial cancer.
Drinking more than four cups of coffee per day was linked with a 25 percent reduced risk for endometrial cancer. Drinking between two and three cups per day was linked with a 7 percent reduced risk.
A similar link was seen in decaffeinated coffee, where drinking more than two cups per day was linked with a 22 percent reduced risk for endometrial cancer.
Giovannucci said he hopes this study will lead to further inquiries about the effect of coffee on cancer because in this and similar studies, coffee intake is self-selected and not randomized.
"Coffee has long been linked with smoking, and if you drink coffee and smoke, the positive effects of coffee are going to be more than outweighed by the negative effects of smoking," said Giovannucci. "However, laboratory testing has found that coffee has much more antioxidants than most vegetables and fruits."
Increased Caffeinated Coffee Consumption Associated With Decreased Risk of Depression in Women
The risk of depression appears to decrease for women with increasing consumption of caffeinated coffee, according to a report in the September 26, 2011 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.
Caffeine is the most frequently used central nervous system stimulant in the world, and approximately 80 percent of consumption is in the form of coffee, according to background information in the article. Previous research, including one prospective study among men, has suggested an association between coffee consumption and depression risk. Because depression is a chronic and recurrent condition that affects twice as many women as men, including approximately one of every five U.S. women during their lifetime, “identification of risk factors for depression among women and the development of new preventive strategies are, theore, a public health priority,” write the authors. They sought to examine whether, in women, consumption of caffeine or certain caffeinated beverages is associated with the risk of depression.
Michel Lucas, Ph.D., R.D., from the Harvard School of Public Health, Boston, and colleagues studied 50,739 U.S. women who participated in the Nurses’ Health Study. Participants, who had a mean (average) age of 63, had no depression at the start of the study in 1996 and were prospectively followed up with through June 2006. Researchers measured caffeine consumption through questionnaires completed from May 1980 through April 2004, including the frequency that caffeinated and noncaffeinated coffee, nonherbal tea, caffeinated soft drinks (sugared or low-calorie colas), caffeine-free soft drinks (sugared or low-calorie caffeine-free colas or other carbonated beverages) and chocolate were usually consumed in the previous 12 months. The authors defined depression as reporting a new diagnosis of clinical depression and beginning regular use of antidepressants in the previous two years.
Analysis of the cumulative mean consumption included a two-year latency period; for example, data on caffeine consumption from 1980 through 1994 were used to predict episodes of clinical depression from 1996 through 1998; consumption from 1980 through 1998 were used for the 1998 through 2000 follow-up period; and so on. During the 10-year follow-up period from 1996 to 2006, researchers identified 2,607 incident (new-onset) cases of depression. When compared with women who consumed one cup of caffeinated coffee or less per week, those who consumed two to three cups per day had a 15 percent decrease in relative risk for depression, and those consuming four cups or more per day had a 20 percent decrease in relative risk. Compared with women in the lowest (less than 100 milligrams [mg] per day) categories of caffeine consumption, those in the highest category (550 mg per day or more) had a 20 percent decrease in relative risk of depression. No association was found between intake of decaffeinated coffee and depression risk.
“In this large prospective cohort of older women free of clinical depression or severe depressive symptoms at baseline, risk of depression decreased in a dose-dependent manner with increasing consumption of caffeinated coffee,” write the authors. They note that this observational study “cannot prove that caffeine or caffeinated coffee reduces the risk of depression but only suggests the possibility of such a protective effect.” The authors call for further investigations to confirm their results and to determine whether usual caffeinated coffee consumption could contribute to prevention or treatment of depre
Coffee Reduces Breast Cancer Risk
Recently published research shows that coffee drinkers enjoy not only the taste of their coffee but also a reduced risk of cancer with their cuppa. More detailed research published May 10, 2011 in BioMed Centrals open access journal Breast Cancer Research shows that drinking coffee specifically reduces the risk of antiestrogen-resistant estrogen-receptor (ER)-negative breast cancer.
Researchers from Sweden compared lifestyle factors and coffee consumption between women with breast cancer and age-matched women without. They found that coffee drinkers had a lower incidence of breast cancer than women who rarely drank coffee. However they also found that several lifestyle factors affected breast cancer rates, such as age at menopause, exercise, weight, education, and a family history of breast cancer. Once they had adjusted their data to account for these other factors they found that the protective effect of coffee on breast cancer was only measurable for ER-negative breast cancer.
The group from Karolinska Institutet explained that, "There is often conflicting information about the beneficial effects of coffee -- when we compared our results to that of a German study we discovered that their data showed the same trend, but the relationship was much weaker. We suggest that this may have something to do with the way the coffee was prepared, or the type of bean perred. It is unlikely that the protective effect is due to phytoestrogens present in coffee since there was no reduction in the incidence of ER-positive cancer in this study."
So while it is evident that coffee may have beneficial effects in protecting women from ER negative breast cancer the exact mechanism and compounds involved are not yet clear and not all types of coffee are the same.
New evidence that caffeine is a healthful antioxidant in coffee
Scientists are reporting an in-depth analysis of how the caffeine in coffee, tea, and other foods seems to protect against conditions such as Alzheimers disease and heart disease on the most fundamental levels. The report, which describes the chemistry behind caffeines antioxidant effects, appears in ACS The Journal of Physical Chemistry.
Annia Galano and Jorge Rafael León-Carmona describe evidence suggesting that coffee is one of the richest sources of healthful antioxidants in the average persons diet. Some of the newest research points to caffeine (also present in tea, cocoa, and other foods) as the source of powerful antioxidant effects that may help protect people from Alzheimers and other diseases. However, scientists know little about exactly how caffeine works in scavenging the so-called free radicals that have damaging effects in the body. And those few studies sometimes have reached contradictory conclusions.
In an effort to bolster scientific knowledge about caffeine, they present detailed theoretical calculations on caffeines interactions with free radicals. Their theoretical conclusions show "excellent" consistency with the results that other scientists have report from animal and other experiments, bolstering the likelihood that caffeine is, indeed, a source of healthful antioxidant activity in coffee.
Coffee protects against diabetes
Coffee, that morning elixir, may give us an early jump-start to the day, but numerous studies have shown that it also may be protective against type 2 diabetes. Yet no one has really understood why.
Now, researchers at UCLA have discovered a possible molecular mechanism behind coffees protective effect. A protein called sex hormone–binding globulin (SHBG) regulates the biological activity of the bodys sex hormones, testosterone and estrogen, which have long been thought to play a role in the development of type 2 diabetes. And coffee consumption, it turns out, increases plasma levels of SHBG.
Reporting with colleagues in the the journal Diabetes, first author Atsushi Goto, a UCLA doctoral student in epidemiology, and Dr. Simin Liu, a professor of epidemiology and medicine with joint appointments at the UCLA School of Public Health and the David Geffen School of Medicine at UCLA, show that women who drink at least four cups of coffee a day are less than half as likely to develop diabetes as non-coffee drinkers.
When the findings were adjusted for levels of SHBG, the researchers said, that protective effect disappeared.
The American Diabetes Association estimates that nearly 24 million children and adults in the U.S. — nearly 8 percent of the population — have diabetes. Type 2 diabetes is the most common form of the disease and accounts for about 90 to 95 percent of these cases.
Early studies have consistently shown that an "inverse association" exists between coffee consumption and risk for type 2 diabetes, Liu said. That is, the greater the consumption of coffee, the lesser the risk of diabetes. It was thought that coffee may improve the bodys tolerance to glucose by increasing metabolism or improving its tolerance to insulin.
"But exactly how is elusive," said Liu, "although we now know that this protein, SHBG, is critical as an early target for assessing the risk and prevention of the onset of diabetes."
Earlier work by Liu and his colleagues published in the New England Journal of Medicine had identified two mutations in the gene coding for SHBG and their effect on the risk of developing type 2 diabetes; one increases risk while the other decreases it, depending on the levels of SHBG in the blood.
A large body of clinical studies has implicated the important role of sex hormones in the development of type 2 diabetes, and its known that SHBG not only regulates the sex hormones that are biologically active but may also bind to receptors in a variety of cells, directly mediating the signaling of sex hormones.
"That genetic evidence significantly advanced the field," said Goto, "because it indicated that SHBG may indeed play a causal role in affecting risk for type 2 diabetes."
"It seems that SHBG in the blood does lect a genetic susceptibility to developing type 2 diabetes," Liu said. "But we now further show that this protein can be influenced by dietary factors such as coffee intake in affecting diabetes risk — the lower the levels of SHBG, the greater the risk beyond any known diabetes risk factors."
For the study, the researchers identified 359 new diabetes cases matched by age and race with 359 apparently healthy controls selected from among nearly 40,000 women enrolled in the Womens Health Study, a large-scale cardiovascular trial originally designed to evaluate the benefits and risks of low-dose aspirin and vitamin E in the primary prevention of cardiovascular disease and cancer.
They found that women who drank four cups of caffeinated coffee each day had significantly higher levels of SHBG than did non-drinkers and were 56 percent less likely to develop diabetes than were non-drinkers. And those who also carried the protective copy of the SHBG gene appeared to benefit the most from coffee consumption.
When the investigators controlled for blood SHBG levels, the decrease in risk associated with coffee consumption was not significant. This suggests that it is SHBG that mediates the decrease in risk of developing type 2 diabetes, Liu said.
And theres bad news for decaf lovers. "Consumption of decaffeinated coffee was not significantly associated with SHBG levels, nor diabetes risk," Goto said. "So you probably have to go for the octane!"
Coffee may protect against head and neck cancers
Data on the effects of coffee on cancer risk have been mixed. However, results of a recent study add to the brewing evidence that drinking coffee protects against cancer, this time against head and neck cancer.
Full study results are published online first in Cancer Epidemiology, Biomarkers & Prevention, a journal of the American Association for Cancer Research.
Using information from a pooled-analysis of nine studies collected by the International Head and Neck Cancer Epidemiology (INHANCE) consortium, participants who were regular coffee drinkers, that is, those who drank an estimated four or more cups a day, compared with those who were non-drinkers, had a 39 percent decreased risk of oral cavity and pharynx cancers combined.
Data on decaffeinated coffee was too sparse for detailed analysis, but indicated no increased risk. Tea intake was not associated with head and neck cancer risk.
The association is more reliable among those who are frequent, regular coffee drinkers, consuming more than four cups of coffee a day.
"Since coffee is so widely used and there is a relatively high incidence and low survival rate of these forms of cancers, our results have important public health implications that need to be further addressed," said lead researcher Mia Hashibe, Ph.D., assistant professor in the department of family and preventive medicine at the University of Utah, Salt Lake City, and a Huntsman Cancer Institute investigator.
"What makes our results so unique is that we had a very large sample size, and since we combined data across many studies, we had more statistical power to detect associations between cancer and coffee," she said.
At the AACR Frontiers in Cancer Prevention Research Conference last December, researchers from Harvard presented data that showed a strong inverse association between coffee consumption and the risk of lethal and advanced prostate cancers — men who drank the most coffee had a 60 percent lower risk of aggressive prostate cancer than men who did not drink any coffee.
More recently, results of another study published in the January issue of Cancer Epidemiology, Biomarkers & Prevention showed a decreased risk of gliomas, or brain tumors, associated with coffee. This association was found among those who drank five or more cups of coffee or tea a day, according the researchers from the Imperial College, London.
Cancer Epidemiology, Biomarkers & Prevention editorial board member Johanna W. Lampe, Ph.D., R.D., believes this current analysis by Hashibe and colleagues provides strong, additional evidence for an association between caffeinated coffee drinking and cancer risk.
"The fact that this was seen for oral and pharyngeal cancers, but not laryngeal cancers, provides some evidence as to a possible specificity of effect," said Lampe, who is a full member and associate division director in the division of public health sciences at Fred Hutchinson Cancer Research Center, Seattle., Wash.
"These findings provide further impetus to pursue research to understand the role of coffee in head and neck cancer prevention," she added. Lampe is not associated with this study.
Additional research is warranted to characterize the importance of timing and duration of exposure and possible mechanisms of action, according to Hashibe.
Coffee = Reduced Risk of Heart Rhythm Disturbances
Coffee drinkers may be less likely to be hospitalized for heart rhythm disturbances, according to a study by the Kaiser Permanente Division of Research in Oakland, Calif. The researchers note that the findings may be surprising because patients frequently report palpitations after drinking coffee.
While it has been established that very large doses of caffeine, the most active ingredient in coffee, can produce rhythm disturbances, there has been limited epidemiologic research about the caffeine doses people take. Previous data from a population study in Denmark compared heavy to light coffee drinkers with respect to risk of atrial fibrillation, the most common major rhythm disturbance, and found no statistically significant difference. This research presentation is believed to be the first large, multiethnic population study to look at all major types of heart rhythm disturbance, the researchers said.
The researchers followed 130,054 men and women and found that those who reported drinking four or more cups of coffee each day had an 18 percent lower risk of hospitalization for heart rhythm disturbances. Those who reported drinking one to three cups each day had a 7 percent reduction in risk, according to Arthur Klatsky, MD, the studys lead investigator and a senior consultant in cardiology at Kaiser Permanente Division of Research in Oakland, Calif.
"Coffee drinking is related to lower risk of hospitalization for rhythm problems, but the association does not prove cause and effect, or that coffee has a protective effect," Klasky said. Other explanations for the association might include other traits of coffee drinkers such as exercise or dietary habits. Additionally, some people with heart rhythm problems often are not hospitalized.
"However, these data might be reassuring to people who drink moderate amounts of coffee that their habit is not likely to cause a major rhythm disturbance," Klatsky said. While this report is not sufficient evidence to say that people should drink coffee to prevent rhythm problems, it supports the idea that people who are at risk for rhythm problems, or who have rhythm problems, do not necessarily need to abstain from coffee, emphasized Klatsky.
The long-term observational study involved 130,054 men and women, 18 to 90 years old, with the majority less than 50 years old. About 2 percent (3,317) were hospitalized for rhythm disturbances; 50 percent of those were for atrial fibrillation, the most common heart rhythm problem. The 18 percent reduction in risk was consistent among men and women, different ethnic groups, smokers and nonsmokers. It also was similar for various rhythm problems such as paroxysmal supraventricular tachycardia, atrial flutter, and atrial fibrillation.
Fourteen percent of the people in the study drank less than one cup of coffee a day; 42 percent drank one to three cups of coffee a day; and 17 percent reported drinking four cups or more each day. Only 27 percent of the people in the study were not coffee drinkers.
While emphasizing that these observational data do not establish causality and a protective mechanism is unclear, researchers speculate that moderate doses of caffeine may affect rhythm disturbances by antagonism of adenosine, a nucleoside compound widely distributed in the body. In the heart adenosine has several effects on conduction of electrical impulses, muscle cell energetics, and heart muscle cell recovery that might predispose to rhythm problems. Caffeine antagonizes adenosine effects by blocking its chemical sites of action.
The researchers examined hospitalization data by elapsed time after the initial examination. For hospitalization within 10 years, the reduction in hospitalizations for people who consumed four cups of coffee or more each day reached 28 percent.
The researchers also studied persons in the group with or without symptoms or history of heart and respiratory disease. For both groups, consuming four cups of coffee daily appeared to be associated with fewer hospitalizations for rhythm disturbances.
Coffee Consumption = Reduced Risk of Diabetes
Drinking more coffee (regular or decaffeinated) or tea appears to lower the risk of developing type 2 diabetes, according to an analysis of previous studies reported in the December 14/28 2009 issue of Archives of Internal Medicine, JAMA
By the year 2025, approximately 380 million individuals worldwide will be affected by type 2 diabetes (1).
Despite considerable research attention, the role of specific dietary and lifestyle factors remains uncertain, although obesity and physical inactivity have consistently been reported to raise the risk of diabetes mellitus. A previously published meta-analysis suggested drinking more coffee may be linked with a reduced risk, but the amount of available information has more than doubled since.
Rachel Huxley, D.Phil, of The George Institute for International Health, University of Sydney, Australia, and colleagues identified 18 studies involving 457,922 participants and assessing the association between coffee consumption and diabetes risk published between 1966 and 2009.
Six studies involving 225,516 individuals also included information about decaffeinated coffee, whereas seven studies with 286,701 participants reported on tea consumption.
When the authors combined and analyzed the data, they found that each additional cup of coffee consumed in a day was associated with a 7 percent reduction in the excess risk of diabetes.
Individuals who drank three to four cups per day had an approximately 25 percent lower risk than those who drank between zero and two cups per day.
In addition, in the studies that assessed decaffeinated coffee consumption, those who drank more than three to four cups per day had about a one-third lower risk of diabetes than those who drank none. Those who drank more than three to four cups of tea had a one-fifth lower risk than those who drank no tea.
That the apparent protective effect of tea and coffee consumption appears to be independent of a number of potential confounding variables raises the possibility of direct biological effects, the authors write. Because of the association between decaffeinated coffee and diabetes risk, the association is unlikely to be solely related to caffeine. Other compounds in coffee and tea including magnesium, antioxidants known as lignans or chlorogenic acids may be involved, the authors note.
If such beneficial effects were observed in interventional trials to be real, the implications for the millions of individuals who have diabetes mellitus, or who are at future risk of developing it, would be substantial, they conclude. For example, the identification of the active components of these beverages could open up therapeutic options for the primary prevention of diabetes mellitus. The findings also pose the question of whether patients most at risk for diabetes mellitus may in the future be advised to increase their consumption of tea and coffee in addition to increasing their levels of physical activity.
Spokesperson for the European Society of Cardiology, Professor Lars Rydén (Sweden), who is a diabetes specialist had the following advice: "This is a cautiously and caully conducted meta-analysis which means authors have caully conducted studies although each are too small to give an answer to the question although they indicate a positive correlation between the consumption of coffee and a decreasing occurrence of diabetes. So the principle is that if you drink coffee whether it is decaffeinated or not, you have less chance of developing diabetes. The data has been strengthened by bringing several studies together.
There are sometimes claims that coffee may do harm, that it may increase the propensity to Cardiovascular disease, but there is no evidence for this. The message is that people may drink coffee safely. Coffee from this point of view may actually be of benefit, as well as reducing the risk of getting diabetes – although the reduction is small (around 7%)."
However Prof Rydén warns that lifestyle changes far outweigh a regular coffee intake.
"Coffee helps, but other things are even more important. Those who are overweight should reduce their bodyweight by 5-10% - not too much - and include physical activity such as a brisk walk for 30 minutes a day. Then those people who are at risk of developing diabetes will reduce this risk by 40-50%.
It is interesting to consider why a beverage like coffee has a beneficial effect. It is obviously not the caffeine as decaffeinated coffee has the same efficiency as caffeinated coffee. Coffee may contain antioxidants but the studies have not measured the number of chemicals in the blood which is important."
Coffee Consumption Associated with Reduced Risk of Advanced Prostate Cancer
While it is too early for physicians to start advising their male patients to take up the habit of regular coffee drinking, data presented at the American Association for Cancer Research Frontiers in Cancer Prevention Research Conference revealed a strong inverse association between coffee consumption and the risk of lethal and advanced prostate cancers.
“Coffee has effects on insulin and glucose metabolism as well as sex hormone levels, all of which play a role in prostate cancer. It was plausible that there may be an association between coffee and prostate cancer,” said Kathryn M. Wilson, Ph.D., a postdoctoral fellow at the Channing Laboratory, Harvard Medical School and the Harvard School of Public Health.
In a prospective investigation, Wilson and colleagues found that men who drank the most coffee had a 60 percent lower risk of aggressive prostate cancer than men who did not drink any coffee. This is the first study of its kind to look at both overall risk of prostate cancer and risk of localized, advanced and lethal disease.
“Few studies have looked prospectively at this association, and none have looked at coffee and specific prostate cancer outcomes,” said Wilson. “We specifically looked at different types of prostate cancer, such as advanced vs. localized cancers or high-grade vs. low-grade cancers.”
Caffeine is actually not the key factor in this association, according to Wilson. The researchers are unsure which components of the beverage are most important, as coffee contains many biologically active compounds like antioxidants and minerals.
Using the Health Professionals’ Follow-Up Study, the researchers documented the regular and decaffeinated coffee intake of nearly 50,000 men every four years from 1986 to 2006; 4,975 of these men developed prostate cancer over that time. They also examined the cross-sectional association between coffee consumption and levels of circulating hormones in blood samples collected from a subset of men in the cohort.
“Very few lifestyle factors have been consistently associated with prostate cancer risk, especially with risk of aggressive disease, so it would be very exciting if this association is confirmed in other studies,” said Wilson. “Our results do suggest there is no reason to stop drinking coffee out of any concern about prostate cancer.”
This association might also help understand the biology of prostate cancer and possible chemoprevention measures.
Coffee W/O Milk Fights Bad Breath
We all know why Starbucks puts boxes of breath mints close to the cash register. Your morning latte can create a startling aroma in your mouth, strong enough to startle your co-workers too.
But intriguing research from Tel Aviv University by renowned breath specialist Prof. Mel Rosenberg of TAUs Sackler Faculty of Medicine finds that a coffee extract can inhibit the bacteria that lead to bad breath. laboratory tests have shown that the extract prevents malodorous bacteria from making their presence felt — or smelt.
"Everybody thinks that coffee causes bad breath," says Prof. Rosenberg, "and its often true, because coffee, which has a dehydrating effect in the mouth, becomes potent when mixed with milk, and can ferment into smelly substances."
But not always. "Contrary to our expectations, we found some components in coffee that actually inhibit bad breath," explains Prof. Rosenberg.
In the laboratory, the team monitored the bacterial odor production of coffee in saliva. In the study, three different brands of coffee were tested: the Israeli brand Elite coffee, Landwer Turkish coffee, and Tasters Choice. Prof. Rosenberg expected to demonstrate the malodor-causing effect of coffee in an in vitro saliva assay developed by Dr. Sarit Levitan in his laboratory. To his surprise, the extracts had the opposite effect.
"The lesson we learned here is one of humility," says Prof. Rosenberg. "We expected coffee would cause bad breath, but there is something inside this magic brew that has the opposite effect."
Prof. Rosenberg would love to isolate the bacterial-inhibiting molecule in order to reap the biggest anti-bacterial benefits from coffee. "Its not the raw extract we will use, he says, "but an active material within it." His latest discovery could be the foundation for an entirely class of mouthwash, breath mints and gum. Purified coffee extract can be added to a breath mint to stop bacteria from forming, stopping bad breath at its source, instead of masking the smell with a mint flavor.
Prof. Rosenberg is a successful scientist and inventor who has already developed a popular mouthwash sold widely in Europe, a pocket-based breath test, and an anti-odor chewing gum.
Caffeine reduces pain during exercise
Stopping to smell the coffee – and enjoy a cup of it – before your morning workout might do more than just get your juices flowing. It might keep you going for reasons you havent even considered.
As a former competitive cyclist, University of Illinois kinesiology and community health professor Robert Motl routinely met his teammates at a coffee shop to fuel up on caffeine prior to hitting the pavement on long-distance training rides.
"The notion was that caffeine was helping us train harder … to push ourselves a little harder," he said.
The cyclists didnt know why it helped, they just knew it was effective.
"I think intuitively a lot of people are taking caffeine before a workout and they dont realize the actual benefit theyre experiencing. That is, theyre experiencing less pain during the workout," Motl said.
He said its becoming increasingly common for athletes – before competing – to consume a variety of substances that include caffeine, motivated by "the notion that it will help you metabolize fat more readily."
"That research isnt actually very compelling," Motl said. "Whats going on in my mind is … people are doing it for that reason, but they actually take that substance that has caffeine and they can push themselves harder. It doesnt hurt as much."
The U. of I. professor has been investigating the relationship between caffeine and physical activity since taking a slight detour during his doctoral-student days, when his work initially was focused on exploring possible links between caffeine intake, spinal lexes and physical activity.
Seven years later, with several studies considering the relationship between physical activity and caffeine behind him, Motl has a much better understanding of why that cuppa Joe he used to consume before distance training and competing enhanced his cycling ability.
Early in his research, he became aware that "caffeine works on the adenosine neuromodulatory system in the brain and spinal cord, and this system is heavily involved in nociception and pain processing." Since Motl knew caffeine blocks adenosine from working, he speculated that it could reduce pain.
A number of studies by the U. of I. professor support that conclusion, including investigations considering such variables as exercise intensity, dose of caffeine, anxiety sensitivity and gender.
Motls latest published study on the effects of caffeine on pain during exercise appears in the April edition of the International Journal of Sport Nutrition and Exercise Metabolism.
"This study looks at the effects of caffeine on muscle pain during high-intensity exercise as a function of habitual caffeine use," he said. "No one has examined that before.
"What we saw is something we didnt expect: caffeine-naïve individuals and habitual users have the same amount of reduction in pain during exercise after caffeine (consumption)."
The studys 25 participants were fit, college-aged males divided into two distinct groups: subjects whose everyday caffeine consumption was extremely low to non-existent, and those with an average caffeine intake of about 400 milligrams a day, the equivalent of three to four cups of coffee.
After completing an initial exercise test in the lab on an ergometer, or stationary cycle, for determination of maximal oxygen consumption or aerobic power, subjects returned for two monitored high-intensity, 30-minute exercise sessions.
An hour prior to each session, cyclists – who had been instructed not to consume caffeine during the prior 24-hour period – were given a pill. On one occasion, it contained a dose of caffeine measuring 5 milligrams per kilogram of body weight (equivalent to two to three cups of coffee); the other time, they received a placebo.
During both exercise periods, subjects perceptions of quadriceps muscle pain was recorded at regular intervals, along with data on oxygen consumption, heart rate and work rate.
"Whats interesting," Motl said, "is that when we found that caffeine tolerance doesnt matter, we were perplexed at first. Then we looked at reviews of the literature relative to caffeine and tolerance effects across a variety of other stimuli. Sometimes you see them, sometimes you dont. That is, sometimes regular caffeine use is associated with a smaller response, whereas, other times, its not."
No ones been able to figure out the reason for the inconsistency, Motl said.
"Clearly, if you regularly consume caffeine, you have to have more to have that bigger, mental-energy effect. But the tolerance effect is not ubiquitous across all stimuli. Even brain metabolism doesnt show this tolerance-type effect. That is, with individuals who are habitual users versus non-habitual users, if you give them caffeine and do brain imaging, the activation is identical. Its really interesting why some processes show tolerance and others dont."
Regarding the outcome of the current research, he said, "it may just be that pain during exercise doesnt show tolerance effects to caffeine."
Motl said one of the next logical steps for his research team would be to conduct studies with rodents in order to better understand the biological mechanism for caffeine in reducing pain.
"If we can get at the biological mechanism, we can begin to understand why there may or may not be this kind of tolerance."
Motl said another research direction might be to determine caffeines effect on sport performance.
"Weve shown that caffeine reduces pain reliably, consistently during cycling, across different intensities, across different people, different characteristics. But does that reduction in pain translate into an improvement in sport performance?"
Meanwhile, the current research could prove encouraging for a range of people, including the average person who wants to become more physically active to realize the health benefits.
"One of the things that may be a practical application, is if you go to the gym and you exercise and it hurts, you may be prone to stop doing that because pain is an aversive stimulus that tells you to withdraw. So if we could give people a little caffeine and reduce the amount of pain theyre experiencing, maybe that would help them stick with that exercise.
"Maybe then theyll push a little harder as well … maybe get even better adaptations to the exercise."
Higher Coffee Consumption Associated with Lower Liver Cancer Risk
A large, prospective population-based study confirms an inverse relationship between coffee consumption and liver cancer risk. The study also found that higher levels of gamma-glutamyltransferase (GGT) in the blood were associated with an increased risk of developing the disease. These findings are published in the July issue of Hepatology, a journal published by John Wiley & Sons on behalf of the American Association for the Study of Liver Diseases (AASLD). The article and an accompanying editorial are also available online at Wiley Interscience (www.interscience.wiley.com).
Researchers led by Gang Hu at the University of Helsinki set out to examine the associations between coffee consumption and serum GGT with the risk of liver cancer in a large prospective cohort. Residents of Finland drink more coffee per capita than the Japanese, Americans, Italians, and other Europeans, so Hu and colleagues studied 60,323 Finnish participants ages 25 to 74 who were cancer-free at baseline. The Finns were included in seven independent cross-sectional population surveys conducted between 1972 and 2002 and followed up through June 2006.
The participants completed a mail-in questionnaire about their medical history, socioeconomic factors and dietary and lifestyle habits. For a subset of participants, clinical data was available, including serum levels of GGT. Data on subsequent cancer diagnoses was collected from the country-wide Finnish Cancer Registry.
Based on their answers to the question: “How many cups of coffee do you drink daily?” the participants were divided into five categories: 0-1 cup, 2-3 cups, 4-5 cups, 6-7 cups, and 8 or more cups per day. After a median follow-up period of 19.3 years, 128 participants were diagnosed with liver cancer.
The researchers noted a significant inverse association between coffee drinking and the risk of primary liver cancer. They found that the multivariable hazards ratio of liver cancer dropped for each group that drank more coffee. It fell from 1.00, to .66, to .44, to .38 to .32 respectively. “The biological mechanisms behind the association of coffee consumption with the risk of liver cancer are not known,” the authors point out.
They also found that high levels of serum GGT were associated with an increased risk of liver cancer. The hazard ratio of liver cancer for the highest vs. lowest quartile of serum GGT was 3.13. “Nevertheless,” they report, “the inverse association between coffee consumption and the risk of liver cancer was consistent in the subjects at any level of serum GGT.”
An accompanying editorial by Carlo La Vecchia of Milan says that Hu’s study solidly confirms the inverse relationship between coffee drinking and liver cancer risk, though we still don’t know if it is causal. “Furthermore, the study by Hu et al. provides original and important quantitative evidence that the levels of GGT are related to subsequent incidence of liver cancer, with an overall relative risk of 2.3,” he says.
La Vecchia notes, however, that, “It remains difficult, however, to translate the inverse relation between coffee drinking and liver cancer risk observed in epidemiological studies into potential implications for prevention of liver cancer by increasing coffee consumption.”
Coffee could protect against Alzheimers disease
A daily dose of caffeine blocks the disruptive effects of high cholesterol that scientists have linked to Alzheimers disease. A study in the open access publication, Journal of Neuroinflammation revealed that caffeine equivalent to just one cup of coffee a day could protect the blood-brain barrier (BBB) from damage that occurred with a high-fat diet.
The BBB protects the central nervous system from the rest of the bodys circulation, providing the brain with its own regulated microenvironment. Previous studies have shown that high levels of cholesterol break down the BBB which can then no longer protect the central nervous system from the damage caused by blood borne contamination. BBB leakage occurs in a variety of neurological disorders such as Alzheimers disease.
In this study, researchers from the University of North Dakota School of Medicine and Health Sciences gave rabbits 3 mg caffeine each day – the equivalent of a daily cup of coffee for an average-sized person. The rabbits were fed a cholesterol-enriched diet during this time.
After 12 weeks a number of laboratory tests showed that the BBB was significantly more intact in rabbits receiving a daily dose of caffeine.
“Caffeine appears to block several of the disruptive effects of cholesterol that make the blood-brain barrier leaky,” says Jonathan Geiger, University of North Dakota School of Medicine and Health Sciences. “High levels of cholesterol are a risk factor for Alzheimers disease, perhaps by compromising the protective nature of the blood-brain barrier. For the first time we have shown that chronic ingestion of caffeine protects the BBB from cholesterol-induced leakage.”
Caffeine appears to protect BBB breakdown by maintaining the expression levels of tight junction proteins. These proteins bind the cells of the BBB tightly to each other to stop unwanted molecules crossing into the central nervous system.
The findings confirm and extend results from other studies showing that caffeine intake protects against memory loss in aging and in Alzheimer’s disease.
“Caffeine is a safe and readily available drug and its ability to stabilise the blood-brain barrier means it could have an important part to play in therapies against neurological disorders,” says Geiger.
Coffee drinkers have slightly lower death rates than people who do not drink coffee
A study published in Annals of Internal Medicine has good news for coffee drinkers: Regular coffee drinking (up to 6 cups per day) is not associated with increased deaths in either men or women. In fact, both caffeinated and decaffeinated coffee consumption is associated with a somewhat smaller rate of death from heart disease.
"Coffee consumption has been linked to various beneficial and detrimental health effects, but data on its relation with death were lacking," says Esther Lopez-Garcia, PhD, the studys lead author. "Coffee consumption was not associated with a higher risk of mortality in middle-aged men and women. The possibility of a modest benefit of coffee consumption on heart disease, cancer, and other causes of death needs to be further investigated."
Women consuming two to three cups of caffeinated coffee per day had a 25 percent lower risk of death from heart disease during the follow-up period (which lasted from 1980 to 2004 and involved 84,214 women) as compared with non-consumers, and an 18 percent lower risk of death caused by something other than cancer or heart disease as compared with non-consumers during follow-up. For men, this level of consumption was associated with neither a higher nor a lower risk of death during the follow-up period (which lasted from 1986 to 2004 and involved 41,736 men).
The researchers analyzed data of 84,214 women who had participated in the Nurses Health Study and 41,736 men who had participated in the Health Professionals Follow-up Study. To be in the current study, participants had to have been free of cancer and heart disease at the start of those larger studies.
The study participants completed questionnaires every two to four years that included questions about how frequently they drank coffee, other diet habits, smoking, and health conditions. The researchers then compared the frequency of death from any cause, death due to heart disease, and death due to cancer among people with different coffee-drinking habits.
Among women, 2,368 deaths were due to heart disease, 5,011 were due to cancer, and 3,716 were due to another cause. Among men, 2,049 deaths were due to heart disease, 2,491 were due to cancer, and 2,348 were due to another cause.
While accounting for other risk factors, such as body size, smoking, diet, and specific diseases, the researchers found that people who drank more coffee were less likely to die during the follow-up period. This was mainly because of lower risk for heart disease deaths among coffee drinkers.
The researchers found no association between coffee drinking and cancer deaths. These relationships did not seem to be related to caffeine because people who drank decaffeinated coffee also had lower death rates than people who did not drink coffee.
The editors of Annals of Internal Medicine caution that the design of the study does not make it certain that coffee decreases the chances of dying sooner than expected. Something else about coffee drinkers might be protecting them. And some measurement error in the assessment of coffee consumption is inevitable because estimated consumption came from self-reports.
In women, caffeine may protect memory
Caffeine may help older women protect their thinking skills, according to a study published in the August 7, 2007, issue of Neurology, the medical journal of the American Academy of Neurology.
The study found that women age 65 and older who drank more than three cups of coffee (or the equivalent in tea) per day had less decline over time on tests of memory than women who drank one cup or less of coffee or tea per day. The results held up even after researchers adjusted for other factors that could affect memory abilities, such as age, education, disability, depression, high blood pressure, medications, cardiovascular disease, and other chronic illnesses.
“Caffeine is a psychostimulant which appears to reduce cognitive decline in women,” said study author Karen Ritchie,. “While we have some ideas as to how this works biologically, we need to have a better understanding of how caffeine affects the brain before we can start promoting caffeine intake as a way to reduce cognitive decline. But the results are interesting – caffeine use is already widespread and it has fewer side effects than other treatments for cognitive decline, and it requires a relatively small amount for a beneficial effect.”
The study involved 7,000 people whose cognitive abilities and caffeine consumption were evaluated over four years. Compared to women who drank one cup or less of coffee per day, those who drank over three cups were less likely to show as much decline in memory. Moreover, the benefits increased with age – coffee drinkers being 30 percent less likely to have memory decline at age 65 and rising to 70 percent less likely over age 80.
Caffeine consumers did not seem to have lower rates of dementia. “We really need a longer study to look at whether caffeine prevents dementia; it might be that caffeine could slow the dementia process rather than preventing it,” said Ritchie.
Ritchie said researchers aren’t sure why caffeine didn’t show the same result in men. “Women may be more sensitive to the effects of caffeine,” she said. “Their bodies may react differently to the stimulant, or they may metabolize caffeine differently.”
Caffeine may prevent heart disease death in elderly
Habitual intake of caffeinated beverages provides protection against heart disease mortality in the elderly, say researchers at SUNY Downstate Medical Center and Brooklyn College._
Using data from the first federal National Health and Nutrition Examination Survey Epidemiologic Follow-up Study, the researchers found that survey participants 65 or more years old with higher caffeinated beverage intake exhibited lower relative risk of coronary vascular disease and heart mortality than did participants with lower caffeinated beverage intake.__
John Kassotis, MD, associate professor of medicine at SUNY Downstate, said, "The protection against death from heart disease in the elderly afforded by caffeine is likely due to caffeines enhancement of blood pressure."_
The protective effect also was found to be dose-responsive: the higher the caffeine intake the stronger the protection. The protective effect was found only in participants who were not severely hypertensive. No significant protective effect was in patients below the age of 65.
Coffee consumption may lower blood uric acid levels
High uric acid levels in the blood are a precursor of gout, the most common inflammatory arthritis in adult men. It is believed that coffee and tea consumption may affect uric acid levels but only one study has been conducted to date. A large-scale study published in the June 2007 issue of Arthritis Care & Research (http://www.interscience.wiley.com/journal/arthritiscare) examined the relationship between coffee, tea, caffeine intake, and uric acid levels and found that coffee consumption is associated with lower uric acid levels but that this appears to be due to components other than caffeine.
Coffee is one of the most widely consumed beverages in the world; more than 50 percent of Americans drink it at the average rate of 2 cups per day. Because of this widespread consumption, its potential effects have important implications for public and individual health. Led by Hyon K. Choi, of the University of British Columbia in Vancouver, Canada, the current study was based on the U.S. Third National Health and Nutrition Examination Survey, conducted between 1988 and 1994. It included over 14,000 men and women at least 20 years old who consented to a medical exam in which blood and urine specimens were obtained. Coffee and tea consumption were determined based on responses to a food questionnaire that assessed intake over the previous month. Researchers estimated the amount of caffeine per cup of coffee or tea using data from the U.S. Department of Agriculture.
The results showed that levels of uric acid in the blood significantly decreased with increasing coffee intake, but not with tea intake. In addition, there was no association between total caffeine intake from beverages and uric acid levels. These results were similar to those found in the only previous study on the topic, which was conducted in Japan. Interestingly, there was an association between decaffeinated coffee consumption and uric acid levels. "These findings suggest that components of coffee other than caffeine contribute to the observed inverse association between coffee intake and uric acid levels," the researchers state.
A recent study found that coffee was associated lower C peptide levels (a marker of insulin levels). The researchers in the current study suggest that because there is a strong relationship between insulin resistance and elevated uric acid levels, the decreased insulin levels associated with coffee consumption may lead to lower uric acid levels. Coffee is also a major source of chlorogenic acid, a strong antioxidant, which may improve insulin sensitivity. Chlorogenic acid also helps inhibit glucose absorption in the intestine; in another study decaffeinated coffee seemed to delay intestinal absorption of glucose and increase concentrations of glucagon-like peptide 1, which is well known for its beneficial effects on insulin secretion and action. The researchers note further that their results could be due to an effect of non-caffeine components found in coffee, which would also explain why coffee affected uric acid levels but tea did not.
To examine how coffee consumption might aggravate or protect against this common and excruciatingly painful condition, researchers at the Arthritis Research Centre of Canada, University of British Columbia in Canada, Brigham and Women’s Hospital, Harvard Medical School, and Harvard School of Public Health in Boston conducted a prospective study on 45,869 men over age 40 with no history of gout at baseline. Over 12 years of follow-up, Hyon K. Choi, MD, DrPH, and his associates evaluated the relationship between the intake of coffee and the incidence of gout in this high risk population. Their findings, featured in the June 2007 issue of Arthritis & Rheumatism (http://www.interscience.wiley.com/journal/arthritis), provide compelling evidence that drinking 4 or more cups of coffee a day dramatically reduces the risk of gout for men.
Subjects were drawn from an ongoing study of some 50,000 male health professionals, 91 percent white, who were between 40 and 75 years of age in 1986 when the project was initiated. To assess coffee and total caffeine intake, Dr. Choi and his team used a food-frequency questionnaire, updated every 4 years. Participants chose from 9 frequency responses – ranging from never to 2 to 4 cups per week to 6 or more per day – to record their average consumption of coffee, decaffeinated coffee, tea, and other caffeine-containing comestibles, such as cola and chocolate.
Through another questionnaire, the researchers documented 757 newly diagnosed cases meeting the American College of Rheumatology criteria for gout during the follow-up period. Then, they determined the relative risk of incident gout for long-term coffee drinkers divided into 4 groups – less than 1 cup per day, 1 to 3 cups per day, 4 to 5 cups per day, and 6 or more cups per day – as well as for regular drinkers of decaffeinated coffee, tea, and other caffeinated beverages. They also evaluated the impact of other risk factors for gout – body mass index, history of hypertension, alcohol use, and a diet high in red meat and high-fat dairy foods among them – on the association between coffee consumption and gout among the study participants.
Most significantly, the data revealed that the risk for developing gout decreased with increasing coffee consumption. The risk of gout was 40 percent lower for men who drank 4 to 5 cups a day and 59 percent lower for men who drank 6 or more cups a day than for men who never drank coffee. There was also a modest inverse association with decaffeinated coffee consumption. These findings were independent of all other risk factors for gout. Tea drinking and total caffeine intake were both shown to have no effect on the incidence of gout among the subjects. On the mechanism of these findings, Dr. Choi speculates that components of coffee other than caffeine may be responsible for the beverage’s gout-prevention benefits. Among the possibilities, coffee contains the phenol chlorogenic acid, a strong antioxidant.
While not prescribing 4 or more cups a day, this study can help individuals make an informed choice regarding coffee consumption. "Our findings are most directly generalizable to men age 40 years and older, the most gout-prevalent population, with no history of gout," Dr. Choi notes. "Given the potential influence of female hormones on the risk of gout in women and an increased role of dietary impact on uric acid levels among patients with existing gout, prospective studies of these populations would be valuable."
Moderate coffee drinking reduces many risks
Although the American Society for Nutrition’s popular “controversy session” at Experimental Biology 2007 focuses on the health effects of coffee drinking, panel chair Dr. James Coughlin, a toxicology/safety consultant at Coughlin & Associates, says that recent advances in epidemiologic and experimental knowledge have transformed many of the negative health myths about coffee drinking into validated health benefits.
Indeed, panel co-chair Dan Steffen, who follows coffee and health issues in the Scientific and Regulatory Affairs group of Kraft Foods, note that the “controversy” is often to educate a wider audience about this transformation in understanding.
Coffee is among the most widely consumed beverages in the world, and Dr. Coughlin says that the preponderance of scientific evidence - some by the panelists - suggests that moderate coffee consumption (3-5 cups per day) may be associated with reduced risk of certain disease conditions, such as Parkinson’s disease. Some research in neuropharamacology suggests that one cup of coffee can halve the risk of Parkinson’s disease. Other studies have found it reduces the risk of Alzheimers disease, kidney stones, gallstones, depression and even suicide.
Dr. Coughlin and two distinguished researchers discussed some of the benefits - and a couple of the remaining increased risk factors (possible increase in blood pressure and plasma homocysteine) - on April 30 at the Experimental Biology meeting in Washington, DC.
Dr. Rob van Dam, an epidemiologist at the Harvard School of Public Health and the Harvard Medical School, studies the link between diet and the development of type 2 diabetes. Worldwide, an estimated 171 million persons have diabetes, mostly type 2 diabetes, and an alarming increase to 366 million persons is expected for the year 2030. While increased physical activity and restriction of energy intake can substantially reduce risk of type 2 diabetes, he believes insight into the role of other lifestyle factors may contribute to additional prevention strategies for type 2 diabetes.
In recent epidemiological studies in the U.S., Europe and Japan, persons who were heavy coffee consumers had a lower risk of type 2 diabetes than persons who consumed little coffee. Interestingly, he says, associations were similar for caffeinated and decaffeinated coffee, suggesting that coffee components other than caffeine may be beneficial for glucose metabolism.
Coffee contains hundreds of components including substantial amounts of chlorogenic acid, caffeine, magnesium, potassium, vitamin B3, trigonelline, and lignans. Limited evidence suggests that coffee may improve glucose metabolism by reducing the rate of intestinal glucose absorption and by stimulating the secretion of the gut hormone glucagon-like peptide-1 (GLP-1) that is beneficial for the secretion of insulin. However, most mechanistic research on coffee and glucose metabolism has been done in animals and in lab tubes and theore metabolic studies in humans are currently being conducted. Further research may lead to the development or selection of coffee types with improved health effects.
Dr. Lenore Arab, a nutritional epidemiologist in the David Geffen School of Medicine at UCLA, notes that the first coffee controversy dates back 430 years when in 1570 some monks petitioned the pope to condemn this drink, so popular among Muslims. Pope Clement VIII, liking how it kept the monks from falling sleep during mass, purportedly blessed it instead. The rest, including the United States’ wholesale conversion to coffee following the Boston Tea Party, is history.
In reviewing the latest epidemiologic literature on cancers and coffee, Dr. Arab has found there to be close to 400 studies of the associations between coffee consumption and cancers various at various sites. The earlier controversy with regard to colon cancer was based on flawed analyses, she says. More thorough analyses and the accumulation of evidence suggest no negative effect on the incidence of colon cancer, and possible protective effects for adenomas of the colon as well as for rectal cancer and liver cancer. Mechanisms which might contribute to a possible anticarcinogenic effect include reduction in cholesterol, bile acid and neutral sterol secretion in the colon, increased colonic motility and reduced exposure of epithelium to carcinogens, the ability of diterpenes to reduce genotoxicity of carcinogens, and lower DNA adduct formation, and the ability of caffeic acid and chlorogenic acid to decreased DNA methylation. In other cancers - breast, ovarian, and prostate - the evidence is not suggestive of either risk or protection. There are two areas, says Dr. Arab, in which there is some evidence of increased risk: leukemia and stomach cancer. The evidence for the former is intriguing, for the latter insubstantial. She concludes that a systematic review of the newer data for liver, rectal, stomach cancer and for childhood leukemia is due.
Study finds that caffeine cuts post-workout pain by nearly 50 percent
Although it’s too soon to recommend dropping by Starbucks before hitting the gym, a study suggests that caffeine can help reduce the post-workout soreness that discourages some people from exercising.
In a study published in the February 2007 issue of The Journal of Pain, a team of University of Georgia researchers finds that moderate doses of caffeine, roughly equivalent to two cups of coffee, cut post-workout muscle pain by up to 48 percent in a small sample of volunteers.
Lead author Victor Maridakis, a researcher in the department of kinesiology at the UGA College of Education, said the findings may be particularly relevant to people to exercise, since they tend to experience the most soreness.
“If you can use caffeine to reduce the pain, it may make it easier to transition from that first week into a much longer exercise program,” he said.
Maridakis and his colleagues studied nine female college students who were not regular caffeine users and did not engage in regular resistance training. One and two days after an exercise session that caused moderate muscle soreness, the volunteers took either caffeine or a placebo and performed two different quadriceps (thigh) exercises, one designed to produce a maximal force, the other designed to generate a sub-maximal force. Those that consumed caffeine one-hour before the maximum force test had a 48 percent reduction in pain compared to the placebo group, while those that took caffeine before the sub-maximal test reported a 26 percent reduction in pain.
Caffeine has long been known to increase alertness and endurance, and a 2003 study led by UGA professor Patrick O’Connor found that caffeine reduces thigh pain during moderate-intensity cycling. O’Connor, who along with professors Kevin McCully and the late Gary Dudley co-authored the current study, explained that caffeine likely works by blocking the body’s receptors for adenosine, a chemical released in response to inflammation.
Despite the positive findings in the study, the researchers say there are some caveats. First, the results may not be applicable to regular caffeine users, since they may be less sensitive to caffeine’s effect. The researchers chose to study women to get a definitive answer in at least one sex, but men may respond differently to caffeine. And the small sample size of nine volunteers means that the study will have to be replicated with a larger study.
O’Connor said that despite these limitations, caffeine appears to be more effective in relieving post-workout muscle pain than several commonly used drugs. Previous studies have found that the pain reliever naproxen (the active ingredient in Aleve) produced a 30 percent reduction in soreness. Aspirin produced a 25 percent reduction, and ibuprofen has produced inconsistent results.
“A lot of times what people use for muscle pain is aspirin or ibuprofen, but caffeine seems to work better than those drugs, at least among women whose daily caffeine consumption is low,” O’Connor said.
Still, the researchers recommend that people use caution when using caffeine before a workout. For some people, too much caffeine can produce side effects such as jitteriness, heart palpitations and sleep disturbances.
“It can reduce pain,” Maridakis said, “but you have to apply some common sense and not go overboard.”
7 Benefits of Pumpkin for health
Tuesday, May 6, 2014
7 Benefits of Pumpkin for health - Pumpkin not only tastes good. But the fruit of the less popular it has many nutrients and vitamins that are essential for your health. A serving of pumpkin once a week can help you to maintain health.
Here are seven health benefits of pumpkin for as reported from magforwomen.com.
1. Healthy digestion
Pumpkin is rich in fiber which can help nourish the digestion. Incorporate pumpkin as one of the menus in your diet can prevent you from digestive problems such as constipation.
2. Good for bone health
Calcium content in it good for bone health. Pumpkin also helps to reduce bone pain caused by arthritis disease osteoporosis.
3. Prevent cancer
Pumpkin high in carotenoids and zinc which can help the body to prevent various types of cancer. The high carotenoids may reduce the risk of prostate cancer.
4. Uplifting
Anchoring both to treat depression because pumpkin seeds are rich in tryptophan and amino acids that can boost your mood. Besides pumpkin can also relieve pain in the body.
5. Boost immunity
Pumpkin can boost immunity as vitamin C in them is quite high. Pumpkin also can function in the body to detox.
6. Good for heart health
Pumpkin can regulate cholesterol levels because the content pitosterolnya .
7. Improve respiratory problems
As one of the foods that contain antioxidants, pumpkins are also able to relieve asthma and help you to have a normal breathing pattern.
Pumpkin turned out to have many health benefits for the body. theore do not hesitate to make a pumpkin as one of your healthy menu.
Here are seven health benefits of pumpkin for as reported from magforwomen.com.
1. Healthy digestion
Pumpkin is rich in fiber which can help nourish the digestion. Incorporate pumpkin as one of the menus in your diet can prevent you from digestive problems such as constipation.
2. Good for bone health
Calcium content in it good for bone health. Pumpkin also helps to reduce bone pain caused by arthritis disease osteoporosis.
3. Prevent cancer
Pumpkin high in carotenoids and zinc which can help the body to prevent various types of cancer. The high carotenoids may reduce the risk of prostate cancer.
4. Uplifting
Anchoring both to treat depression because pumpkin seeds are rich in tryptophan and amino acids that can boost your mood. Besides pumpkin can also relieve pain in the body.
5. Boost immunity
Pumpkin can boost immunity as vitamin C in them is quite high. Pumpkin also can function in the body to detox.
6. Good for heart health
Pumpkin can regulate cholesterol levels because the content pitosterolnya .
7. Improve respiratory problems
As one of the foods that contain antioxidants, pumpkins are also able to relieve asthma and help you to have a normal breathing pattern.
Pumpkin turned out to have many health benefits for the body. theore do not hesitate to make a pumpkin as one of your healthy menu.
Health Benefits of White and Green Tea Consumption
Tuesday, April 22, 2014
I try to drink 4 cups of strong white tea daily (with a little orange juice.) Heres why:
Health Benefits of White and Green Tea Consumption
White Tea vs. Green Tea
When discussing white tea vs green tea, it is important to realize that they both come from the same plant, the tea plant Camellia sinensis. The main difference between the two types of tea is that the white tea leaves are harvested at a younger age than the green tea leaves. They both undergo very little processing. White tea is not fermented at all, while green tea is partly fermented. By contrast, black tea is fully fermented. Because they are so gently treated, white tea and green tea retain their content of beneficial antioxidants.
Antioxidants
However, studies have shown that the young, white tea leaves retain antioxidants in higher concentrations than green tea does. Studies have shown that white tea has a concentration of antioxidants that is three times higher than in green tea. Essentially, white tea contains the same concentrations of antioxidants as the young and fresh tea leaf buds that are still attached to the bush. This makes white tea the tea with the highest antioxidant content, which for many is the main reason for drinking white tea. For comparison, one cup of white tea contains approximately twelve (12) times as much antioxidants as fresh orange juice.
Caffeine
White tea contains less caffeine than green tea, about 15 mg per serving compared to the 20 mg for green tea. If caffeine tends to make you jittery, white tea may be the better choice.
Benefits
In general, any benefit attributed to green tea is probably even stronger in white tea.
White Tea Beats Green Tea In Fighting Germs
New studies conducted at Pace University have indicated that White Tea Extract (WTE) may have prophylactic applications in retarding growth of bacteria that cause Staphylococcus infections, Streptococcus infections, pneumonia and dental caries. Researchers presented their findings May 25, 2004 at the 104th General Meeting of the American Society for Microbiology.
"Past studies have shown that green tea stimulates the immune system to fight disease," says Milton Schiffenbauer, Ph.D., a microbiologist and professor in the Department of Biology at Pace Universitys Dyson College of Arts & Sciences and primary author of the research. "Our research shows White Tea Extract can actually destroy in vitro the organisms that cause disease. Study after study with tea extract proves that it has many healing properties. This is not an old wives tale, its a fact."
White tea was more effective than green tea at inactivating bacterial viruses. Results obtained with the bacterial virus, a model system; suggest that WTE may have an anti-viral effect on human pathogenic viruses. The addition of White Tea Extract to various toothpastes enhanced the anti-microbial effect of these oral agents.
Studies have also indicated that WTE has an anti-fungal effect on Penicillium chrysogenum and Saccharomyces cerevisiae. In the presence of WTE, Penicillium spores and Saccharomyces cerevisiae yeast cells were totally inactivated. It is suggested that WTE may have an anti-fungal effect on pathogenic fungi.
Several findings in the new study are of particular interest:
* The anti-viral and anti-bacterial effect of white tea (Stash and Templar brands) is greater than that of green tea.
* The anti-viral and anti-bacterial effect of several toothpastes including Aim, Aquafresh, Colgate, Crest and Orajel was enhanced by the addition of white tea extract.
* White tea extract exhibited an anti-fungal effect on both Penicillium chrysogenum and Saccharomyces cerevisiae.
• White tea extract may have application in the inactivation of pathogenic human microbes, i.e., bacteria, viruses, and fungi.
White Tea Helps Weight Loss
Possible anti-obesity effects of white tea have been demonstrated in a series of experiments on human fat cells (adipocytes). Researchers writing in BioMed Centrals open access journal Nutrition and Metabolism have shown that an extract of the herbal brew effectively inhibits the generation of new adipocytes and stimulates fat mobilization from mature fat cells.
Marc Winnefeld led a team of researchers from Beiersdorf AG, Germany, who studied the biological effects of an extract of white tea – the least processed version of the tea plant Camellia sinensis. He said, "In the industrialized countries, the rising incidence of obesity-associated disorders including cardiovascular diseases and diabetes constitutes a growing problem. Weve shown that white tea may be an ideal natural source of slimming substances".
After treating lab-cultured human pre-adipocytes with the tea extract, the authors found that fat incorporation during the genesis of new adipocytes was reduced. According to Winnefeld, "The extract solution induced a decrease in the expression of genes associated with the growth of new fat cells, while also prompting existing adipocytes to break down the fat they contain".
White tea is made from the buds and first leaves of the plant used to make green tea and the black tea most commonly drunk in Western countries. It is less processed than the other teas and contains more of the ingredients thought to be active on human cells, such as methylxanthines (like caffeine) and epigallocatechin-3-gallate (EGCG) – which the authors believe to be responsible for many of the anti-adipogenic effects demonstrated in their study.
Article: White Tea extract induces lipolytic activity and inhibits adipogenesis in human subcutaneous (pre)-adipocytes _Jörn Söhle, Anja Knott, Ursula Holtzmann, Ralf Siegner, Elke Grönniger, Andreas Schepky, Stefan Gallinat, Horst Wenck, Franz Stäb and Marc Winnefeld _Nutrition & Metabolism article available at the journal website: http://www.nutritionandmetabolism.com/
Citrus Juice, Vitamin C Give Staying Power to Green Tea Antioxidants
To get more out of your next cup of tea, just add juice.
A study found that citrus juices enable more of green teas unique antioxidants to remain after simulated digestion, making the pairing even healthier than previously thought.
The study compared the effect of various beverage additives on catechins, naturally occurring antioxidants found in tea. Results suggest that complementing green tea with either citrus juices or vitamin C likely increases the amount of catechins available for the body to absorb.
Catechins (pronounced KA-teh-kins), display health-promoting qualities and may be responsible for some of green teas reported health benefits, like reduced risk of cancer, heart attack and stroke. The problem, Ferruzzi said, is that catechins are relatively unstable in non-acidic environments, such as the intestines, and less than 20 percent of the total remains after digestion.
"Off the bat you are eliminating a large majority of the catechins from plain green tea," Ferruzzi said. "We have to address this fact if we want to improve bodily absorption."
Ferruzzi tested juices, creamers and other additives that are either commonly added to fresh-brewed tea or used to make ready-to-drink tea products by putting them through a model simulating gastric and small-intestinal digestion. Citrus juice increased recovered catechin levels by more than five times, the study found. Ascorbic acid, or vitamin C, used to increase shelf life in ready-to-drink products, increased recovered levels of the two most abundant catechins by sixfold and 13-fold, respectively.
Lemons and tea go even better together than their popularity might suggest. Lemon juice caused 80 percent of teas catechins to remain, the study found. Following lemon, in terms of stabilizing power, were orange, lime and grapefruit juices. Ferruzzi said both vitamin C and citrus juices must interact with catechins to prevent their degradation in the intestines, although data made it clear that citrus juices have stabilizing effects beyond what would be predicted solely based on their vitamin C content.
"If you want more out of your green tea, add some citrus juice to your cup after brewing or pick a ready-to-drink product formulated with ascorbic acid," Ferruzzi said.
Ready-to-drink green tea products should optimally contain 100-200 mg of catechins, but oftentimes do not have sufficient levels of tea extract since some people do not like green teas flavor, Ferruzzi said.
Milk eliminates cardiovascular health benefits of tea
Research published in the European Heart Journal has found that the protective effect that tea has on the cardiovascular system is totally wiped out by adding milk.
Tests on volunteers showed that black tea significantly improves the ability of the arteries to relax and expand, but adding milk completely blunts the effect. Supporting tests on rat aortas (aortic rings) and endothelial (lining) cells showed that tea relaxed the aortic rings by producing nitric oxide, which promotes dilation of blood vessels. But, again, adding milk blocked the effect.
The findings, by cardiologists and scientists from the Charité Hospital, Universitätsmedizin-Berlin, Germany, are bad news for tea-drinking nations like the British, who normally add milk to their beverage. The results have led the researchers to suggest that tea drinkers who customarily add milk should consider omitting it some of the time.
Their study showed that the culprit in milk is a group of proteins called caseins, which they found interacted with the tea to decrease the concentration of catechins in the beverage. Catechins are the flavonoids in tea that mainly contribute to its protection against cardiovascular disease.
Senior researcher Dr Verena Stangl, Professor of Cardiology (Molecular Atherosclerosis) at the hospital, said: “There is a broad body of evidence from experimental and clinical studies indicating that tea exerts antioxidative, anti-inflammatory and vasodilating effects, thereby protecting against cardiovascular diseases. As worldwide tea consumption is second only to that of water, its beneficial effects represent an important public health issue. But, up to now, it’s not been known whether adding milk to tea, as widely practised in the UK and some other countries, influences these protective properties. So, we decided to investigate the effects of tea, with and without milk, on endothelial function, because that is a sensitive indicator of what is happening to blood vessels.”
Sixteen healthy postmenopausal women drank either half a litre of freshly brewed black tea, black tea with 10% skimmed milk, or boiled water (as a control) on three separate occasions under the same conditions. The endothelial function of the brachial artery in the forearm was measured by high resolution ultrasound before and two hours after drinking, with measurements being taken every 15 seconds for up to two minutes a time.
Said first author Dr Mario Lorenz, a molecular biologist: “We found that, whereas drinking tea significantly increased the ability of the artery to relax and expand to accommodate increased blood flow compared with drinking water, the addition of milk completely prevents the biological effect. To extend our findings to a functional model, we determined vasodilation in rat aortic rings by exposing them to tea on its own and tea with individual milk proteins added, and got the same result.”
Milk contains a number of different proteins: by testing each one separately, the researchers found that it was the three caseins that accounted for the inhibiting effect, probably by forming complexes with tea catechins.
Said Dr Stangl: “The well-established benefits of tea have been described in many studies. Our results thus provide a possible explanation for the lack of beneficial effects of tea on the risk of heart disease in the UK, a country where milk is usually added.”
She said their findings could also have implications for cancer, against which tea has also been shown to be protective. “Since milk appears to modify the biological activities of tea ingredients, it is likely that the anti-tumour effects of tea could be affected as well. I think it is essential that we re-examine the association between tea consumption and cancer protection, to see if that is the case.”
Said Dr Lorenz: “It is important to bear in mind that green tea is almost exclusively drunk without milk. So we are talking only about those countries and regions where black tea is consumed and where milk is added. We certainly don’t want to dismiss the consumption of black tea: the results of our study merely attempt to encourage people to consider that, while the addition of milk may improve its taste, it may also lower its health-protective properties.”
Dr Stangl said that another important lesson from their research was that it was vital in nutritional studies to exclude confounding factors as far as possible. Often, the effects of a single nutritional compound or beverage such as red wine, olive oil and so on, are analysed. But, it is difficult to assign clearly the observed effects and separate them from the surrounding food matrix (such as adding milk) that may bias results. It was theore important to collect all data accurately and include potentially confounding factors in the analysis.
She said that the team was now in the process of comparing the effects of green and black tea on vascular function. “It’s an ongoing question whether green tea, with its higher catechin content, is superior to black tea in regard to endothelial function. In addition, because of the antiatherogenic potential of tea ingredients, we want to investigate the effects of the ingredients on chronic cardiovascular processes such as the development of restenosis (re-narrowing of arteries) after catheter procedures.”
Drinking very hot tea can increase the risk of throat cancer
People are advised to wait a few minutes before drinking a cup of freshly-boiled tea today as a new study, published on bmj.com, finds that drinking very hot tea (70°C or more) can increase the risk of cancer of the oesophagus, the muscular tube that carries food from the throat to the stomach.
The study was carried out in northern Iran, where large amounts of hot tea are drunk every day.
But an accompanying editorial says these findings are not cause for alarm and the general advice is to allow foods and beverages to cool a little before swallowing.
Cancers of the oesophagus kill more than 500,000 people worldwide each year and oesophageal squamous cell carcinoma (OSCC) is the commonest type. In Europe and America, it is mainly caused by tobacco and alcohol use and is more common in men than in women, but drinking hot beverages is also thought to be a risk factor.
Golestan Province in northern Iran has one of the highest rates of OSCC in the world, but rates of smoking and alcohol consumption are low and women are as likely to have a diagnosis as men. Tea drinking, however, is widespread, so researchers set out to investigate a possible link between tea drinking habits and risk of OSCC.
They studied tea drinking habits among 300 people diagnosed with OSCC and a matched group of 571 healthy controls from the same area. Nearly all participants drank black tea regularly, with an average volume consumed of over one litre a day.
Compared with drinking warm or lukewarm tea (65°C or less), drinking hot tea (65-69°C) was associated with twice the risk of oesophageal cancer, and drinking very hot tea (70°C or more) was associated with eight-fold increased risk.
Likewise, compared with drinking tea four or more minutes after being poured, drinking tea less than two minutes after pouring was associated with a five-fold higher risk.
There was no association between the amount of tea consumed and risk of cancer.
To minimise errors between reported and actual tea temperatures, the researchers then measured the actual temperature that tea was consumed by nearly 50,000 residents of the same area. This ranged from less than 60°C to more than 70°C and there was a moderate agreement between reported tea drinking temperature and actual temperature measurements.
Our results show a strong increase in the risk of oesophageal squamous cell carcinoma associated with drinking hot or very hot tea, say the authors.
Previous studies from the United Kingdom have reported an average temperature perence of 56-60°C among healthy populations.
They suggest that informing the population about the hazards of drinking hot tea may be helpful in reducing the incidence of oesophageal cancer in Golestan and in other high risk populations where similar habits are prevalent.
These results provide persuasive evidence that drinking tea at temperatures greater than 70°C markedly increases the risk of oesophageal squamous cell carcinoma, says David Whiteman from the Queensland Institute of Medical Research in Australia in an accompanying editorial.
This report also lends support to the notion that thermal injury may be a cause of epithelial cancers, though he points out that the way in which heat promotes tumour development is not clear and warrants further investigation.
However, he stresses that these findings are not cause for alarm, and they should not reduce public enthusiasm for the time honoured ritual of drinking tea. Instead he suggests waiting at least four minutes before drinking a cup of freshly boiled tea, or more generally allowing foods and beverages to cool from "scalding" to "tolerable" before swallowing.
Green tea found to reduce rate of some GI cancers
Women who drink green tea may lower their risk of developing some digestive system cancers, especially cancers of the stomach/esophagus and colorectum, according to a study led by researchers from Vanderbilt-Ingram Cancer Center.
The study by lead author Sarah Nechuta, Ph.D., MPH, assistant professor of Medicine, was published online in advance of the Nov. 1, 2012 edition of the American Journal of Clinical Nutrition. Wei Zheng, M.D., Ph.D., MPH, professor of Medicine, chief of the Division of Epidemiology and director of the Vanderbilt Epidemiology Center, was the principal investigator for the study.
To determine green teas impact on cancer risk, the investigators surveyed women enrolled in the Shanghai Womens Health Study, a population-based study of approximately 75,000 middle-aged and older Chinese women. During the initial interview participants were asked if they drank tea, the type of tea consumed and how much they consumed. Most of the Chinese women reported drinking primarily green tea.
The researchers found that regular tea consumption, defined as tea consumption at least three times a week for more than six months, was associated with a 17 percent reduced risk of all digestive cancers combined. A further reduction in risk was found to be associated with an increased level of tea drinking. Specifically, those who consumed about two to three cups per day (at least 150 grams of tea per month) had a 21 percent reduced risk of digestive system cancers.
The trend toward fewer digestive cancers was strongest for stomach/esophageal and colorectal cancers.
"For all digestive system cancers combined, the risk was reduced by 27 percent among women who had been drinking tea regularly for at least 20 years," said Nechuta. "For colorectal cancer, risk was reduced by 29 percent among the long-term tea drinkers. These results suggest long-term cumulative exposure may be particularly important."
Tea contains polyphenols or natural chemicals that include catechins like EGCG and ECG. Catechins have antioxidant properties and may inhibit cancer by reducing DNA damage and blocking tumor cell growth and invasion.
The researchers also asked about other lifestyle factors including the kinds of food eaten regularly, exercise habits, education level and occupation. Women who had ever smoked or who drank alcohol were excluded from the study.
Regular tea drinkers in the study were younger, had higher education, exercised more and consumed more fruits and vegetables. While the researchers adjusted for these factors, they could not rule out an effect from these and other unmeasured lifestyle habits.
The study was conducted in nonsmoking and nondrinking Chinese women to minimize the potential influence of these two risk factors on the results for tea consumption and digestive system cancer risk.
Green Tea Fights Prostate Cancer
Six cups of green tea a day may slow the progression of prostate cancer, a new study suggests.
The finding stems from research that showed prostate patients scheduled for a type of surgery known as a prostatectomy, where the prostate is removed, reduced their levels of some disease-associated inflammation by drinking lots of brewed green tea in the weeks preceding the operation. And that reduction in inflammation may inhibit tumor growth, the researchers suggested.
Their results were to be presented at the October, 2012 American Association for Cancer Researchs annual prevention conference in Anaheim, Calif.
The notion that the polyphenol compounds found in green tea might have a protective effect against prostate cancer has yet to be confirmed outside a laboratory setting. However, this latest report builds on previous Italian research that suggested that consuming green tea extract may help lower the risk that a precancerous condition will develop into full-blown prostate cancer.
And related research that was also presented at the cancer research conference suggested that the flavonoids found in fruits and vegetables may be associated with a lower risk of developing aggressive prostate cancer.
However, at least one urologist, Dr. Mark Soloway, chairman emeritus of urology at the University of Miami Miller School of Medicine, pointed to the new studys limitations, and said it was too soon to say that green tea had any impact on prostate cancer.
Scientific findings presented at meetings should be viewed as preliminary until published in a peer-reviewed journal.
In this latest green tea study, men who drank the beverage for three to eight weeks prior to surgery experienced a noticeable drop in both serum prostate-specific antigen (PSA) concentrations and PSA protein expression by the time they went under the knife. The fall-off in such telltale signs of disease was accompanied by reductions in both disease-linked inflammation and oxidative DNA damage, the study authors said.
"To see this effect, you would need to drink a lot of green tea," stressed study author Susanne Henning, a registered dietician and adjunct professor with the University of California, Los Angeles David Geffen School of Medicine. "Two cups a day is not going to help. In fact, we had our men drink six cups spread out all throughout the day, which I think was beneficial because green tea polyphenols are excreted very rapidly, so if you drink it that way you keep your levels up. And that seems to be the important factor in keeping the protection going."
To explore the anti-cancer potential of green tea, the authors focused on 67 prostate cancer patients, all of whom were weeks away from surgery. About half the men were randomly assigned to a six-cup-a-day regimen of green tea leading up to surgery, while the others consumed water instead.
The result: Blood and urine samples analyzed alongside tissue samples taken during surgery revealed that the green tea group fared significantly better on key signs of inflammation, PSA levels and expression and DNA damage.
However, no notable difference was found between the two groups in terms of tumor cell growth.
Henning stressed the need for more research on the potential green-tea/prostate cancer connection, and her team is currently planning new animal investigations involving combinations of green tea and other natural foods.
While this research showed an association between green tea and prostate cancer, it did not prove a cause-and-effect link.
"Actually, several food agents have been under investigation for their protective impact," she noted. "Lycopene and omega-3 fatty acids, for example. So, I would say that if you have cancer and you want to make a decision about all of this, then think of incorporating all of those as a part of a lifestyle change. I know that if I was diagnosed with prostate cancer, I would try to change my lifestyle. And that would mean, in addition to eating lots of fruits and vegetables and trying to lose weight and exercising, that I would definitely drink green tea."
The University of Miamis Soloway said that while drinking green tea probably does not have a downside, this "limited study" does not confirm its impact as a prostate cancer intervention.
"[Theres] not much solid data to prove it," he said. "This is a small study, and it would take a longer study with hundreds of patients to prove its benefit."
Soloway also noted that the jury is still out on whether inflammation even plays a significant role in cancer development. "It is very much a question," he said. "Not proven at all."
But, he agreed that until larger studies come along to explore green teas potential, "it might be worth giving it a shot."
Green tea boosts brain cell production to aid memory
It has long been believed that drinking green tea is good for the memory. Now researchers have discovered how the chemical properties of Chinas favorite drink affect the generation of brain cells, providing benefits for memory and spatial learning. The research is published in Molecular Nutrition & Food Research.
"Green tea is a popular beverage across the world," said Professor Yun Bai from the Third Military Medical University, Chongqing, China. "There has been plenty of scientific attention on its use in helping prevent cardiovascular diseases, but now there is emerging evidence that its chemical properties may impact cellular mechanisms in the brain."
Professor Bais team focused on the organic chemical EGCG, (epigallocatechin-3 gallate) a key property of green tea. While EGCG is a known anti-oxidant, the team believed it can also have a beneficial effect against age-related degenerative diseases.
"We proposed that EGCG can improve cognitive function by impacting the generation of neuron cells, a process known as neurogenesis," said Bai. "We focused our research on the hippocampus, the part of the brain which processes information from short-term to long-term memory."
The team found that ECGC boosts the production of neural progenitor cells, which like stem cells can adapt, or differentiate, into various types of cells. The team then used laboratory mice to discover if this increased cell production gave an advantage to memory or spatial learning.
"We ran tests on two groups of mice, one which had imbibed ECGC and a control group," said Bai. "First the mice were trained for three days to find a visible platform in their maze. Then they were trained for seven days to find a hidden platform."
The team found that the ECGC treated mice required less time to find the hidden platform. Overall the results revealed that EGCG enhances learning and memory by improving object recognition and spatial memory.
"We have shown that the organic chemical EGCG acts directly to increase the production of neural progenitor cells, both in glass tests and in mice," concluded Bai. "This helps us to understand the potential for EGCG, and green tea which contains it, to help combat degenerative diseases and memory loss."
Green Tea Compound is Effective in Treating Genetic Disorder and Two Types of Tumors
A compound found in green tea shows great promise for the development of drugs to treat two types of tumors and a deadly congenital disease. The discovery is the result of research led by Principal Investigator, Dr. Thomas Smith at The Donald Danforth Plant Science Center and his colleagues at The Children’s Hospital of Philadelphia. Their findings are published in the recent article, “Green Tea Polyphenols Control Dysregulated Glutamate Dehydrogenase In Transgenic Mice By Hijacking The ADP Activation Site” in The Journal of Biological Chemistry.
Glutamate dehydrogenase (GDH) is found in all living organisms and is responsible for the digestion of amino acids. In animals, GDH is controlled by a complex network of metabolites. For decades it was not clear why animals required such regulation but other kingdoms did not. This was partially answered by the Stanley group’s finding that a deadly congenital disease, hyperinsulinism/hyperammonemia (HHS), is caused by the loss of some of this regulation. In this disorder, patients (typically children) respond to the consumption of protein by over secreting insulin, becoming severely hypoglycemic, often leading to death.
Using atomic structures to understand the differences between animals and plants, Dr. Smith and his colleagues discovered that two compounds found naturally in green tea are able to compensate for this genetic disorder by turning off GDH in isolated and when the green tea compounds were administered orally. The Smith lab also used X-ray crystallography to determine the atomic structure of these green tea compounds bound to the enzyme. With this atomic information, they hope to be able to modify these natural compounds to design and develop better drugs.
Interestingly, two other research groups have validated and extended these findings to demonstrate that blocking GDH with green tea is very effective at killing two different kinds of tumors; glioblastomas, an aggressive type of brain tumor, and tuberous sclerosis complex disorder, a genetic disease that causes non-malignant tumors to grow on a number of organs.
Green tea has a powerful ability to increase the number of “regulatory T cells”
One of the beneficial compounds found in green tea has a powerful ability to increase the number of “regulatory T cells” that play a key role in immune function and suppression of autoimmune disease, according to new research in the Linus Pauling Institute at Oregon State University.
This may be one of the underlying mechanisms for the health benefits of green tea, which has attracted wide interest for its ability to help control inflammation, improve immune function and prevent cancer.
Pharmaceutical drugs are available that perform similar roles and have been the subject of much research, scientists say, but they have problems with toxicity. A natural food product might provide a long-term, sustainable way to accomplish this same goal without toxicity, researchers said.
“This appears to be a natural, plant-derived compound that can affect the number of regulatory T cells, and in the process improve immune function,” said Emily Ho, an LPI principal investigator and associate professor in the OSU Department of Nutrition and Exercise Sciences.
“When fully understood, this could provide an easy and safe way to help control autoimmune problems and address various diseases,” Ho said.
The findings have been published in Immunology Letters, a professional journal.
There are many types of cells that have different roles in the immune system, which is a delicate balancing act of attacking unwanted invaders without damaging normal cells. In autoimmune diseases, which can range from simple allergies to juvenile diabetes or even terminal conditions such as Lou Gehrig’s disease, this process goes awry and the body mistakenly attacks itself.
Some cells exist primarily to help control that problem and dampen or “turn off” the immune system, including regulatory T cells. The number and proper function of those regulatory T cells, in turn, is regulated by other biological processes such as transcription factors and DNA methylation.
In this study, OSU scientists did experiments with a compound in green tea, a polyphenol called EGCG, which is believed to be responsible for much of its health benefits and has both anti-inflammatory and anti-cancer characteristics. They found it could cause a higher production of regulatory T cells. Its effects were not as potent as some of those produced by prescription drugs, but it also had few concerns about long-term use or toxicity.
“EGCG may have health benefits through an epigenetic mechanism, meaning we aren’t changing the underlying DNA codes, but just influencing what gets expressed, what cells get turned on,” Ho said. “And we may be able to do this with a simple, whole-food approach.”
Laboratory studies done with mice, Ho said, showed that treatment with EGCG significantly increased the numbers and frequencies of regulatory T cells found in spleen and lymph notes, and in the process helped to control the immune response.
“Epigenetic regulation can be potentially exploited in generating suppressive regulatory T cells for therapeutic purposes, and is of significant clinical importance for the suppression of autoimmune diseases,” the researchers said in their study.
Green tea enhances bone health and reduces inflammation
Tea has for generations been an integral infusion worldwide, carrying both epicurean and economic significance. But, does it impart honest-to-goodness health benefits? In other words, is its persistence in the human diet perhaps coincident with enhanced quality (or quantity) of life?
Dr. Chwan-Li (Leslie) Shen, an associate professor and a researcher at the Laura W. Bush Institute for Womens Health at the Texas Tech University Health Sciences Center, is convinced that the answer to this question is a resounding yes – especially if the tea is of the "green" variety. Green tea, historically consumed in the Orient and now an international mainstay, is chock full of compounds called polyphenols known for their potent antioxidant activity. Dozens of epidemiological (observational) studies have shown that people who consume the highest levels of green tea polyphenols (GTP) tend to have lower risks of several chronic degenerative diseases such as cardiovascular disease and osteoporosis. These findings have been followed up with animal studies, including some conducted by Shen, suggesting that the mechanism behind this correlation may have to do with lowering chronic levels of inflammation.
Originally from Taiwan, Dr. Shen has now spent over 2 decades studying how and why some Eastern lifestyle norms (such as drinking green tea) might be beneficial for Westerners as well. For instance, she has developed an animal model (the ovariectomized, middle-aged female rat). With this model Dr. Shen and her team can effectively study the effects of green tea consumption on protection against breakdown of the bones microarchitecture. In humans, this can lead to osteoporosis, a condition common to older women. It is Dr Shens hope that what she learns from her animal models might also be applicable to postmenopausal women.
In Shens most recent research, she focused on postmenopausal women and investigated the potential for green tea to work synergistically with tai chi – a traditional Chinese form of moderately intense aerobic fitness activity grounded in mind-body philosophy – in enhancing bone strength. The results of this work, which was funded by the National Institutes of Health/National Center for Complementary and Alternative Medicine, will be presented as a poster at the Experimental Biology meetings on April 10. Carried out as a double-blind, placebo-controlled, intervention trial (the "holy grail" of scientific studies), this experiment involved 171 postmenopausal women (mean age: ~57 y) who had weak bones but not full-fledged osteoporosis. Subjects were divided into 4 groups:
Placebo: starch pill (placebo) and no tai chi
GTP: green tea polyphenols (500 mg/day) and no tai chi
Placebo+TC: starch pill and tai chi (3 times/week)
GTP+TC: green tea polyphenols and tai chi
The study lasted for 6 months, during which time blood and urine samples were collected and muscle strength assessed.
The results show that consumption of GTP (at a level equivalent to about 4-6 cups of steeped green tea daily) and participation in tai chi independently enhanced markers of bone health by 3 and 6 months, respectively. A similar effect was found for muscle strength at the 6-month time point. Participants taking tai chi classes also reported significant beneficial effects in quality of life in terms of improving their emotional and mental health. Perhaps most remarkable, however, was the substantial effect that both GTP and tai chi had on biological markers of oxidative stress. Because oxidative stress is a main precursor to inflammation, this finding suggests that green tea and tai chi may help reduce the underlying etiology of not only osteoporosis, but other inflammatory diseases as well.
Dr. Shen and colleagues concluded that there is a "favorable effect of modest green tea consumption on bone remodeling in this pre-osteoporotic population" and hope to soon complete a more long-term study utilizing more technically savvy measures of bone density.
Regularly drinking green tea could protect against Alzheimers and other forms of dementia
Regularly drinking green tea could protect the brain against developing Alzheimers and other forms of dementia, according to latest research by scientists at Newcastle University.
The study, published in the academic journal Phytomedicine, also suggests this ancient Chinese remedy could play a vital role in protecting the body against cancer.
Led by Dr Ed Okello, the Newcastle team wanted to know if the protective properties of green tea – which have previously been shown to be present in the undigested, freshly brewed form of the drink – were still active once the tea had been digested.
Digestion is a vital process which provides our bodies with the nutrients we need to survive. But, says Dr Okello, it also means that just because the food we put into our mouths is generally accepted to contain health-boosting properties, we cant assume these compounds will ever be absorbed by the body.
"What was really exciting about this study was that we found when green tea is digested by enzymes in the gut, the resulting chemicals are actually more effective against key triggers of Alzheimers development than the undigested form of the tea," explains Dr Okello, based in the School of Agriculture, Food and Rural Development at Newcastle University.
"In addition to this, we also found the digested compounds had anti-cancer properties, significantly slowing down the growth of the tumour cells which we were using in our experiments."
As part of the research, the Newcastle team worked in collaboration with Dr Gordon McDougall of the Plant Products and Food Quality Group at the Scottish Crop Research Institute in Dundee, who developed technology which simulates the human digestive system.
It is this which made it possible for the team to analyse the protective properties of the products of digestion.
Two compounds are known to play a significant role in the development of Alzheimers disease – hydrogen peroxide and a protein known as beta-amyloid.
Previous studies have shown that compounds known as polyphenols, present in black and green tea, possess neuroprotective properties, binding with the toxic compounds and protecting the brain cells.
When ingested, the polyphenols are broken down to produce a mix of compounds and it was these the Newcastle team tested in their latest research.
"Its one of the reasons why we have to be so caul when we make claims about the health benefits of various foods and supplements," explains Dr Okello.
"There are certain chemicals we know to be beneficial and we can identify foods which are rich in them but what happens during the digestion process is crucial to whether these foods are actually doing us any good."
Carrying out the experiments in the lab using a tumour cell model, they exposed the cells to varying concentrations of the different toxins and the digested green tea compounds.
Dr Okello explained: "The digested chemicals protected the cells, preventing the toxins from destroying the cells.
"We also saw them affecting the cancer cells, significantly slowing down their growth.
"Green tea has been used in Traditional Chinese medicine for centuries and what we have here provides the scientific evidence why it may be effective against some of the key diseases we face today."
The next step is to discover whether the beneficial compounds are produced during digestion after healthy human volunteers consume tea polyphenols. The team has already received funding from the Biotechnology and Biological Sciences Research Council (BBSRC) to take this forward.
Dr Okello adds: "There are obviously many factors which together have an influence on diseases such as cancer and dementia - a good diet, plenty of exercise and a healthy lifestyle are all important."
High and moderate consumption of tea are linked with reduced heart disease
High and moderate consumption of tea are linked with reduced heart disease, according to a study published in Arteriosclerosis, Thrombosis, and Vascular Biology: Journal of the American Heart Association.
Researchers in The Netherlands found:
Drinking more than six cups of tea per day was associated with a 36 percent lower risk of heart disease compared to those who drank less than one cup of tea per day.
Drinking three to six cups of tea per day was associated with a 45 percent reduced risk of death from heart disease, compared to consumption of less than one cup per day.
Red wine and green tea halt prostate cancer growth
In what could lead to a major advance in the treatment of prostate cancer, scientists now know exactly why polyphenols in red wine and green tea inhibit cancer growth. This new discovery, published online in The FASEB Journal (http://www.fasebj.org), explains how antioxidants in red wine and green tea produce a combined effect to disrupt an important cell signaling pathway necessary for prostate cancer growth. This finding is important because it may lead to the development of drugs that could stop or slow cancer progression, or improve current treatments.
"Not only does SphK1/S1P signaling pathway play a role in prostate cancer, but it also plays a role in other cancers, such as colon cancer, breast cancer, and gastric cancers," said Gerald Weissmann, MD, editor-in-chief of The FASEB Journal. "Even if future studies show that drinking red wine and green tea isnt as effective in humans as we hope, knowing that the compounds in those drinks disrupts this pathway is an important step toward developing drugs that hit the same target."
Scientists conducted in vitro experiments which showed that the inhibition of the sphingosine kinase-1/sphingosine 1-phosphate (SphK1/S1P) pathway was essential for green tea and wine polyphenols to kill prostate cancer cells. Next, mice genetically altered to develop a human prostate cancer tumor were either treated or not treated with green tea and wine polyphenols. The treated mice showed reduced tumor growth as a result of the inhibited SphK1/S1P pathway. To mimic the preventive effects of polyphenols, another experiment used three groups of mice given drinking water, drinking water with a green tea compound known as EGCg, or drinking water with a different green tea compound, polyphenon E. Human prostate cancer cells were implanted in the mice and results showed a dramatic decrease in tumor size in the mice drinking the EGCg or polyphenon E mixtures.
"The profound impact that the antioxidants in red wine and green tea have on our bodies is more than anyone would have dreamt just 25 years ago," Weissmann added. "As long as they are taken in moderation, all signs show that red wine and green tea may be ranked among the most potent health foods we know."
Green tea may help fight glaucoma and other eye diseases
Scientists have confirmed that the healthful substances found in green tea — renowned for their powerful antioxidant and disease-fighting properties — do penetrate into tissues of the eye. Their new report, the first documenting how the lens, retina, and other eye tissues absorb these substances, raises the possibility that green tea may protect against glaucoma and other common eye diseases. "Green Tea Catechins and Their Oxidative Protection in the Rat Eye" appears in ACSs bi-weekly Journal of Agricultural and Food Chemistry.
Chi Pui Pang and colleagues point out that so-called green tea "catechins" have been among a number of antioxidants thought capable of protecting the eye. Those include vitamin C, vitamin E, lutein, and zeaxanthin. Until now, however, nobody knew if the catechins in green tea actually passed from the stomach and gastrointestinal tract into the tissues of the eye.
Pang and his colleagues resolved that uncertainty in experiments with laboratory rats that drank green tea. Analysis of eye tissues showed beyond a doubt that eye structures absorbed significant amounts of individual catechins. The retina, for example, absorbed the highest levels of gallocatechin, while the aqueous humor tended to absorb epigallocatechin. The effects of green tea catechins in reducing harmful oxidative stress in the eye lasted for up to 20 hours. "Our results indicate that green tea consumption could benefit the eye against oxidative stress," the report concludes.
Green tea fights lung cancer risk for smokers
Drinking green tea could modulate the effect of smoking on lung cancer. Results of this hospital-based, randomized study conducted in Taiwan were presented at the AACR-IASLC Joint Conference on Molecular Origins of Lung Cancer, held there from Jan. 11-14, 2010.
"Lung cancer is the leading cause of all cancer deaths in Taiwan," said I-Hsin Lin, M.S., a student at Chung Shan Medical University in Taiwan. "Tea, particularly green tea, has received a great deal of attention because tea polyphenols are strong antioxidants, and tea preparations have shown inhibitory activity against tumorigenesis."
However, previous studies of green tea have been inhibited by the flaws of the epidemiologic model with its inherent biases.
Lin and colleagues enrolled 170 patients with lung cancer and 340 healthy patients as controls. The researchers administered questionnaires to obtain demographic characteristics, cigarette smoking habits, green tea consumption, dietary intake of fruits and vegetables, cooking practices and family history of lung cancer. They also performed genotyping on insulin-like growth factors as polymorphisms on the following insulin-like growth factors: IGF1, IGF2 and IGFBP3, which have all been reported to be associated with cancer risk.
Among smokers and non-smokers, those who did not drink green tea had a 5.16-fold increased risk of lung cancer compared with those who drank at least one cup of green tea per day. Among smokers, those who did not drink green tea at all had a 12.71-fold increased risk of lung cancer compared with those who drank at least one cup of green tea per day.
Lin and colleagues suspect genetics may play a role in this risk differential. Green tea drinkers with non-susceptible IGF1 (CA)19/(CA)19 and (CA)19/X genotypes reported a 66 percent reduction in lung cancer risk as compared with green tea drinkers carrying the IGF1 X/X genotype.
Heavy smokers carrying susceptible IGF1, IGF2 and IGFBP3 genotypes also had a higher risk of lung cancer compared with nonsmokers carrying non-susceptible IGF1, IGF2 and IGFBP3 genotypes.
"Our study may represent a clue that in the case of lung cancer, smoking-induced carcinogenesis could be modulated by green tea consumption and the growth factor environment," said Lin.
Green tea fights oral cancer
Green tea extract has shown promise as cancer prevention agent for oral cancer in patients with a pre-malignant condition known as oral leukoplakia, according to researchers at The University of Texas M. D. Anderson Cancer Center.
The study, published online in Cancer Prevention Research, is the first to examine green tea as a chemopreventative agent in this high-risk patient population. The researchers found that more than half of the oral leukoplakia patients who took the extract had a clinical response.
Long investigated in laboratory, epidemiological and clinical settings for several cancer types, green tea is rich in polyphenols, which have been known to inhibit carcinogenesis in preclinical models. Still, clinical results have been mixed.
"While still very early, and not definitive proof that green tea is an effective preventive agent, these results certainly encourage more study for patients at highest risk for oral cancer," said Vassiliki Papadimitrakopoulou, M.D., professor in M. D. Andersons Department of Thoracic/Head and Neck Medical Oncology, and the studys senior author. "The extracts lack of toxicity is attractive - in prevention trials, its very important to remember that these are otherwise healthy individuals and we need to ensure that agents studied produce no harm."
In the Phase II dose-finding study, 41 M. D. Anderson oral leukoplakia patients were randomized between August 2002 and March 2008 to receive either green tea extract or placebo. Participants took the extract, an oral agent, for three months at one of three doses - 500 per meter squared of body mass (mg/m2); 750 mg/m2 or 1,000 mg/m2 - three times daily. To best assess biomarkers, participants also underwent a baseline and 12-week biopsy, an important component in the design of the study, the researchers say.
"Collecting oral tissue biopsies was essential in that it allowed us to learn that not only did the green tea extract appear to have benefit for some patients, but we pointed to anti-angiogenic effects as a potential mechanism of action," said Anne Tsao, M.D., assistant professor in the Department of Thoracic/Head and Neck Medical Oncology, and the studys first author. "While preliminary because our patient population was so small, this gives us direction for further study."
Of those taking green tea at the two highest doses, 58.8 percent had a clinical response, compared with 36.4 percent in the lowest extract dose and 18.2 percent in the placebo arm. At an extended follow-up with a mean of 27.5 months, 15 participants had developed oral cancer, with a median time to disease development of 46.4 months.
Although not statistically significant, the green tea extract also improved histology and trended towards an improvement in a number of biomarkers that may play a vital role in predicting cancer development.
Another important finding, say the researchers, was that that the extract was well tolerated. Side effects, including insomnia and nervousness, were mostly seen in the high-dose group but produced no significant toxicity.
"While these are encouraging findings, much more research must be done before we can conclude that green tea may prevent oral or any other type of cancer. Its also important to remind people that this trial enrolled very few participants who, at the highest dose levels took the equivalent of eight cups of green tea three times a day," said Papadimitrakopoulo. "We need to further understand if green tea offers longer-term prevention effects for patients."
Papadimitrakopoulo and Tsao think that future studies with green tea in this high-risk population should focus on participants being exposed to the supplement for a longer time period. The researchers also stressed that the green tea extract studied in this trial was never sold over-the-counter and/or the Internet, both of which are not highly regulated. Rather, the compound was exclusively developed as a pharmaceutical.
According to the American Cancer Society, more than 35,720 are expected to be diagnosed with oral and/or pharynx cancer and the five year survival rate is less than 50 percent.
Green tea may help improve bone health
Researchers in Hong Kong are reporting new evidence that green tea — one of the most popular beverages consumed worldwide and now available as a dietary supplement — may help improve bone health. They found that the tea contains a group of chemicals that can stimulate bone formation and help slow its breakdown. Their findings are in ACS Journal of Agricultural and Food Chemistry, a bi-weekly publication. The beverage has the potential to help in the prevention and treatment of osteoporosis and other bone diseases that affect million worldwide, the researchers suggest.
In the new study, Ping Chung Leung and colleagues note that many scientific studies have linked tea to beneficial effects in preventing cancer, heart disease, and other conditions. Recent studies in humans and cell cultures suggest that tea may also benefit bone health. But few scientific studies have explored the exact chemicals in tea that might be responsible for this effect.
The scientists exposed a group of cultured bone-forming cells (osteoblasts) to three major green tea components — epigallocatechin (EGC), gallocatechin (GC), and gallocatechin gallate (GCG) — for several days. They found that one in particular, EGC, boosted the activity of a key enzyme that promotes bone growth by up to 79 percent. EGC also significantly boosted levels of bone mineralization in the cells, which strengthens bones. The scientists also showed that high concentrations of ECG blocked the activity of a type of cell (osteoclast) that breaks down or weakens bones. The green tea components did not cause any toxic effects to the bone cells, they note.
Green tea fights several kinds of cancer
A large new review of studies that examined the affect of green tea on cancer prevention has yielded promising results.
Researchers looked at 51 medium- to high-quality studies that included more than 1.6 million participants. The studies focused on the relationship between green tea consumption and a variety of cancers, including breast, lung, digestive tract, urological prostate, gynecological and oral cancers.
The comprehensive review analyzed studies conducted from 1985 through 2008. Many of the reviewed studies took place in Asia, where tea drinking is widespread and part of the daily routine for many.
Three types of tea — black, green and oolong — come from the plant Camellia sinensis, and all contain polyphenols. Catechins, a subgroup of the polyphenols, are powerful antioxidants. Some say the polyphenols in green tea are unique, preventing cell growth and thus having the potential to prevent cancer.
The review found that green tea had limited benefits for liver cancer, but found conflicting evidence for other gastrointestinal cancers, such as cancer of the esophagus, colon or pancreas. One study found a decreased risk of prostate cancer for men who consumed higher quantities of green tea or its extracts.
The review did not find any benefit for preventing death from gastric cancer, and found that green tea might even increase the risk of urinary bladder cancer. Despite conflicting findings, there was “limited moderate to strong evidence” of a benefit for lung, pancreatic and colorectal cancer. None of the studies that simply observed a group of people over time found a benefit for breast cancer prevention. However, both of the case control studies — which compare people without a condition to people with it — found a positive association between green tea consumption and a decreased risk of breast cancer.
Nagi Kumar, Ph.D., director of Nutrition Research at Moffitt Cancer Center in Tampa, Fla., is optimistic about the potential for green tea in cancer prevention. “The substances found in green tea are certainly promising,” Kumar said. “The field now has progressed to where we [can]…test the effectiveness and safety of green tea polyphenols using a drug form similar to the constituents in tea to see if we can prevent cancer progression. Time will tell.”
Kumar said the Cochrane review was “more an inventory of studies completed rather than a systematic scientific review,” adding that “the discussion lacks a scientific approach in the interpretation of the discordant findings.”
Kumar also noted that several groups are conducting randomized clinical trials, including one comprising six institutions: the Moffitt Cancer Center and the James A Haley VA Medical Center, University of Chicago, Jefferson in Philadelphia, University of Florida and Louisiana State University.
Both scientists agreed that more research is a good idea. Boehm said she highly recommends the conduction of a large, well-designed, study with adequate green tea consumption levels.
“The review provides where we have been in this field of research and where we are going and how much more we have on hand,” Kumar said. “Although not as thorough as I would like it, it is a good quality review.”
Theore, while the questions about green tea consumption and cancer prevention remain unanswered, one thing remains clear: It is fine to consume green tea if you enjoy it and it might prove beneficial in the over time.
“If not exceeding the daily recommended allowance those who enjoy a cup of green tea should continue its consumption,” Boehm said. “Drinking green tea appears to be safe at regular, habitual and moderate use at its recommended dosage of up to 1200 ml/day.” That comes to a little over five cups a day.
Green tea fights prostate cancer
According to results of a study published in Cancer Prevention Research, a journal of the American Association for Cancer Research, men with prostate cancer who consumed the active compounds in green tea demonstrated a significant reduction in serum markers predictive of prostate cancer progression.
"The investigational agent used in the trial, Polyphenon E (provided by Polyphenon Pharma) may have the potential to lower the incidence and slow the progression of prostate cancer," said James A. Cardelli, Ph.D., professor and director of basic and translational research in the Feist-Weiller Cancer Center, LSU Health Sciences Center-Shreveport.
Green tea is the second most popular drink in the world, and some epidemiological studies have shown health benefits with green tea, including a reduced incidence of prostate cancer, according to Cardelli. However, some human trials have found contradictory results. The few trials conducted to date have evaluated the clinical efficacy of green tea consumption and few studies have evaluated the change in biomarkers, which might predict disease progression.
Cardelli and colleagues conducted this open-label, single-arm, phase II clinical trial to determine the effects of short-term supplementation with green teas active compounds on serum biomarkers in patients with prostate cancer. The biomarkers include hepatocyte growth factor (HGF), vascular endothelial growth factor (VEGF) and prostate specific antigen (PSA). HGF and VEGF are good prognostic indicators of metastatic disease.
The study included 26 men, aged 41 to 72 years, diagnosed with prostate cancer and scheduled for radical prostatectomy. Patients consumed four capsules containing Polyphenon E until the day before surgery — four capsules are equivalent to about 12 cups of normally brewed concentrated green tea, according to Cardelli. The time of study for 25 of the 26 patients ranged from 12 days to 73 days, with a median time of 34.5 days.
Findings showed a significant reduction in serum levels of HGF, VEGF and PSA after treatment, with some patients demonstrating reductions in levels of greater than 30 percent, according to the researchers.
Cardelli and colleagues found that other biomarkers were also positively affected. There were only a few reported side effects associated with this study, and liver function remained normal.
Results of a recent year-long clinical trial conduced by researchers in Italy demonstrated that consumption of green tea polyphenols reduced the risk of developing prostate cancer in men with high-grade prostate intraepithelial neoplasia (HGPIN).
"These studies are just the beginning and a lot of work remains to be done, however, we think that the use of tea polyphenols alone or in combination with other compounds currently used for cancer therapy should be explored as an approach to prevent cancer progression and recurrence," Cardelli said.
William G. Nelson, V., M.D., Ph.D., professor of oncology, urology and pharmacology at the Johns Hopkins Kimmel Cancer Center, believes the reduced serum biomarkers of prostate cancer may be attributable to some sort of benefit relating to green tea components.
"Unfortunately, this trial was not a randomized trial, which would have been needed to be more sure that the observed changes were truly attributable to the green tea components and not to some other lifestyle change (better diet, taking vitamins, etc.) men undertook in preparation for surgery," added Nelson, who is also a senior editor for Cancer Prevention Research. However, "this trial is provocative enough to consider a more substantial randomized trial."
In collaboration with Columbia University in New York City, the researchers are currently conducting a comparable trial among patients with breast cancer. They also plan to conduct further studies to identify the factors that could explain why some patients responded more dramatically to Polyphenon E than others. Cardelli suggested that additional controlled clinical trials should be done to see if combinations of different plant polyphenols were more effective than Polyphenon E alone.
"There is reasonably good evidence that many cancers are preventable, and our studies using plant-derived substances support the idea that plant compounds found in a healthy diet can play a role in preventing cancer development and progression," said Cardelli.
Green tea found to reduce rate of some GI cancers
Women who drink green tea may lower their risk of developing some digestive system cancers, especially cancers of the stomach/esophagus and colorectum, according to a study led by researchers from Vanderbilt-Ingram Cancer Center.
The study by lead author Sarah Nechuta, Ph.D., MPH, assistant professor of Medicine, was published online in advance of the Nov. 1, 2012 edition of the American Journal of Clinical Nutrition. Wei Zheng, M.D., Ph.D., MPH, professor of Medicine, chief of the Division of Epidemiology and director of the Vanderbilt Epidemiology Center, was the principal investigator for the study.
To determine green teas impact on cancer risk, the investigators surveyed women enrolled in the Shanghai Womens Health Study, a population-based study of approximately 75,000 middle-aged and older Chinese women. During the initial interview participants were asked if they drank tea, the type of tea consumed and how much they consumed. Most of the Chinese women reported drinking primarily green tea.
The researchers found that regular tea consumption, defined as tea consumption at least three times a week for more than six months, was associated with a 17 percent reduced risk of all digestive cancers combined. A further reduction in risk was found to be associated with an increased level of tea drinking. Specifically, those who consumed about two to three cups per day (at least 150 grams of tea per month) had a 21 percent reduced risk of digestive system cancers.
The trend toward fewer digestive cancers was strongest for stomach/esophageal and colorectal cancers.
"For all digestive system cancers combined, the risk was reduced by 27 percent among women who had been drinking tea regularly for at least 20 years," said Nechuta. "For colorectal cancer, risk was reduced by 29 percent among the long-term tea drinkers. These results suggest long-term cumulative exposure may be particularly important."
Tea contains polyphenols or natural chemicals that include catechins like EGCG and ECG. Catechins have antioxidant properties and may inhibit cancer by reducing DNA damage and blocking tumor cell growth and invasion.
The researchers also asked about other lifestyle factors including the kinds of food eaten regularly, exercise habits, education level and occupation. Women who had ever smoked or who drank alcohol were excluded from the study.
Regular tea drinkers in the study were younger, had higher education, exercised more and consumed more fruits and vegetables. While the researchers adjusted for these factors, they could not rule out an effect from these and other unmeasured lifestyle habits.
The study was conducted in nonsmoking and nondrinking Chinese women to minimize the potential influence of these two risk factors on the results for tea consumption and digestive system cancer risk.
Antioxidants in green tea may help reduce periodontal disease
With origins dating back over 4,000 years, green tea has long been a popular beverage in Asian culture, and is increasingly gaining popularity in the United States. And while ancient Chinese and Japanese medicine believed green tea consumption could cure disease and heal wounds, recent scientific studies are beginning to establish the potential health benefits of drinking green tea, especially in weight loss, heart health, and cancer prevention. A study recently published in the Journal of Periodontology, the official publication of the American Academy of Periodontology (AAP), uncovered yet another benefit of green tea consumption. Researchers found that routine intake of green tea may also help promote healthy teeth and gums. The study analyzed the periodontal health of 940 men, and found that those who regularly drank green tea had superior periodontal health than subjects that consumed less green tea.
"It has been long speculated that green tea possesses a host of health benefits," said study author Dr. Yoshihiro Shimazaki of Kyushu University in Fukuoka, Japan. "And since many of us enjoy green tea on a regular basis, my colleagues and I were eager to investigate the impact of green tea consumption on periodontal health, especially considering the escalating emphasis on the connection between periodontal health and overall health."
Male participants aged 49 through 59 were examined on three indicators of periodontal disease: periodontal pocket depth (PD), clinical attachment loss (CAL) of gum tissue, and bleeding on probing (BOP) of the gum tissue. Researchers observed that for every one cup of green tea consumed per day, there was a decrease in all three indicators, theore signifying a lower instance of periodontal disease in those subjects who regularly drank green tea.
Green teas ability to help reduce symptoms of periodontal disease may be due to the presence of the antioxidant catechin. Previous research has demonstrated antioxidants ability to reduce inflammation in the body, and the indicators of periodontal disease measured in this study, PD, CAL and BOP, suggest the existence of an inflammatory response to periodontal bacteria in the mouth. By interfering with the bodys inflammatory response to periodontal bacteria, green tea may actually help promote periodontal health, and ward off further disease. Periodontal disease is a chronic inflammatory disease that affects the gums and bone supporting the teeth, and has been associated with the progression of other diseases such as cardiovascular disease and diabetes.
"Periodontists believe that maintaining healthy gums is absolutely critical to maintaining a healthy body," says Dr. David Cochran, DDS, PhD, President of the AAP and Chair of the Department of Periodontics at the University of Texas Health Science Center at San Antonio. "That is why it is so important to find simple ways to boost periodontal health, such as regularly drinking green tea – something already known to possess certain health-related benefits."
Green, black tea can reduce stroke risk
Drinking at least three cups of green or black tea a day can significantly reduce the risk of stroke, a new UCLA study has found. And the more you drink, the better your odds of staving off a stroke.
The study results, published in the online edition of Stroke: Journal of the American Heart Association, were presented Feb. 19, 2009 at the American Heart Associations annual International Stroke Conference in San Diego, Calif.
The UCLA researchers conducted an evidence-based review of all human observational studies on stroke and tea consumption found in the PubMed and Web of Science archives. They found nine studies describing 4,378 strokes among nearly 195,000 individuals, according to lead author Lenore Arab, a professor of medicine in the division of general internal medicine and health services research at the David Geffen School of Medicine at UCLA.
"What we saw was that there was a consistency of effect of appreciable magnitude," said Arab, who is also a professor of biological chemistry. "By drinking three cups of tea a day, the risk of a stroke was reduced by 21 percent. It didnt matter if it was green or black tea."
And extrapolating from the data, the effect appears to be linear, Arab said. For instance, if one drinks three cups a day, the risk falls by 21 percent; follow that with another three cups and the risk drops another 21 percent.
This effect was found in tea made from the plant Camellia sinensis, not from herbal teas.
There are very few known ways to reduce the risk of stroke, Arab said. And developing medications for stroke victims is particularly challenging, given that the drug has to get to the stroke-damaged site quickly because damage occurs so fast. Arab said that by the time a stroke victim gets medical care, its nearly too late to impede the damage.
"Thats why these findings are so exciting," she said. "If we can find a way to prevent the stroke, or prevent the damage, that is simple and not toxic, that would be a great advance."
Though no one is certain which compounds in tea are responsible for this effect, researchers have speculated that the antioxidant epigallocatechin gallate (EGCG) or the amino acid theanine may be what helps. Antioxidants are believed to help prevent coronary artery disease.
"And we do know that theanine is nearly 100-percent absorbed," Arab said. "It gets across the blood-brain barrier and it looks a lot like a molecule thats very similar to glutamate, and glutamate release is associated with stroke.
"It could be that theanine and glutamate compete for the glutamate receptor in the brain," she added.
Although a randomized clinical trial is needed to confirm this effect, the findings suggest that drinking three cups of green or black tea a day could help prevent an ischemic stroke.
Green Tea May Help Fight Rheumatoid Arthritis
A new study from the University of Michigan Health System suggests that a compound in green tea may provide therapeutic benefits to people with rheumatoid arthritis.
The study, presented April 29 at the Experimental Biology 2007 in Washington, D.C., looks at a potent anti-inflammatory compound derived from green tea. Researchers found that the compound – called epigallocatechin-3-gallate (EGCG) – inhibited the production of several molecules in the immune system that contribute to inflammation and joint damage in people with rheumatoid arthritis.
The compound from green tea also was found to suppress the inflammatory products in the connective tissue of people with rheumatoid arthritis.
“Our research is a very promising step in the search for therapies for the joint destruction experienced by people who have rheumatoid arthritis,” says Salah-uddin Ahmed, Ph.D., lead researcher on the study. Ahmed, a research investigator with the Division of Rheumatology at the U-M Health System, was selected to present the research at the Experimental Biology meeting as the recipient of the Young Scientist Travel Award, given by the American Society for Pharmacology and Experimental Therapeutics. This study was also selected by the American Society for Nutrition to be featured in a press release.
To conduct the research, the scientists isolated cells called synovial fibroblasts from the joints of patients with rheumatoid arthritis. These fibroblasts – cells that form a lining of the tissue surrounding the capsule of the joints – then were cultured in a growth medium and incubated with the green tea compound.
The fibroblasts were then stimulated with pro-inflammatory cytokine IL-1_, a protein of the immune system known to play an important role in causing joint destruction in people with rheumatoid arthritis.
The researchers looked at whether the green tea compound has the capability to block the activity of two potent molecules, IL-6 and cyclooxygenase-2 (COX-2), which also are actively involved in causing bone erosion in the joints of people with rheumatoid arthritis.
When untreated cells were stimulated with IL-1_, a sequence of molecular events occurred that resulted in production of the bone-destructive molecules. But the scientists found that pre-incubation with EGCG was capable of inhibiting the production of these molecules. EGCG also inhibited the production of prostaglandin E2, a hormone-like substance that causes inflammation in the joints.
The cell signaling pathways that regulate levels of these immune system molecules under both normal and rheumatoid arthritis situations are well studied, and the researchers were able to trace the effects of the green tea compound infusion to see that it worked by inhibiting these pathways.
Ahmed says that these studies suggest that EGCG or molecules that could be derived synthetically from the EGCG found in green tea may be of therapeutic value by inhibiting the joint destruction in rheumatoid arthritis.
Previously, Ahmed and other researchers made another promising finding when EGCG-pretreated synovial fibroblasts were stimulated with the cytokine IL-1_ to study the protective effect of this green tea compound. Compared to untreated synovial fibroblasts, the cells treated with EGCG markedly blocked the ability of IL-1_ to produce the proteins and enzymes that infiltrate the joints of persons with rheumatoid arthritis and cause cartilage degradation.
The laboratory now is focused on the inhibitory role of EGCG in gene expression. The scientists plan to test EGCG in animal models of rheumatoid arthritis to see if it provides similar therapeutic or preventive effects. Ahmed believes that the outcome of these studies will form a strong foundation for future testing of green tea compound in humans with rheumatoid arthritis.
Green tea may help protect against autoimmune disease
Green tea may help protect against autoimmune disease, Medical College of Georgia researchers say.
Researchers studied an animal model for type I diabetes and primary Sjogren’s Syndrome, which damages the glands that produce tears and saliva.
They found significantly less salivary gland damage in a group treated with green tea extract, suggesting a reduction of the Sjogren’s symptom commonly erred to as dry mouth. Dry mouth can also be caused by certain drugs, radiation and other diseases.
Approximately 30 percent of elderly Americans suffer from degrees of dry mouth, says Dr. Stephen Hsu, a researcher in the MCG School of Dentistry and lead investigator on the study. Only 5 percent of the elderly in China, where green tea is widely consumed, suffer from the problem.
“Since it is an autoimmune disease, Sjogren’s Syndrome causes the body to attack itself and produce extra antibodies that mistakenly target the salivary and lacrimal glands,” he says.
There is no cure or prevention for Sjogren’s Syndrome.
Researchers studied the salivary glands of the water-consuming group and a green tea extract-consuming group to look for inflammation and the number of lymphocytes, a type of white blood cells that gather at sites of inflammation to fend off foreign cells.
The group treated with green tea had significantly fewer lymphocytes, Dr. Hsu says. Their blood also showed lower levels of autoantibodies, protein weapons produced when the immune system attacks itself, he says.
Researchers already know that one component of green tea – EGCG – helps suppress inflammation, according to Dr. Hsu.
“So, we suspected that green tea would suppress the inflammatory response of this disease. Those treated with the green tea extract beginning at three weeks, showed significantly less damage to those glands over time.”
These results, published in a recent issue of Autoimmunity, reinforced findings of a 2005 study showing a similar phenomenon in a Petrie dish, Dr. Hsu says.
Researchers also suspect that the EGCG in green tea can turn on the body’s defense system against TNF-alpha – a group of proteins and molecules involved in systemic inflammation.
TNF-alpha, which is produced by white blood cells, can reach out to target and kill cells.
“The salivary gland cells treated with EGCG had much fewer signs of cell death caused by TNF-alpha,” Dr. Hsu says. “We don’t yet know exactly how EGCG makes that happen. That will require further study. In some ways, this study gives us more questions than answers.”
Further study could help determine green tea’s protective role in other autoimmune diseases, including lupus, psoriasis, scleroderma and rheumatoid arthritis, he says.
Green tea may protect from inflamed bladder
Herbal agents could be used to treat inflammatory bladder diseases, according to a preliminary study that looked at the ability of green tea to protect bladder cells from inflammation. The University of Pittsburgh School of Medicine study, being presented at the 2007 annual meeting of the American Urological Association (AUA) in Anaheim, Calif., found that components of green tea protected bladder cells from damage in culture. The study is Abstract 299 in the AUA proceedings.
Green tea, reported to have many health benefits, is rich in powerful antioxidants that make it a possible remedy for many medical conditions. It is comprised of catechins – plant metabolites that provide it with many anti-oxidative properties.
"We discovered that catechins found in green tea protected both normal and cancerous bladder cells from inflammation when we exposed the cells to hydrogen peroxide," said Michael B. Chancellor, M.D., professor of urology and gynecology at the University of Pittsburgh School of Medicine. "Although further studies are needed, these results indicate herbal supplements from green tea could be a treatment option for various bladder conditions that are caused by injury or inflammation."
In the study, normal and cancerous bladder cells were exposed to two major catechin components of green tea, epigallocatechin gallate (EGCG) and epicatechin gallate (ECG), for 23 hours. Both significantly protected cell lines from exposure to hydrogen peroxide, which damages or kills cells. The concentrations of EGCG and ECG used in the study were at levels that may be achieved through dietary intake.
Approximately ten million American adults have problems controlling their bladders. Bladder disease affects both men and women and can include incontinence or interstitial cystitis, a chronic inflammatory condition that causes frequent, urgent and painful urination and pelvic discomfort.
Green tea may protect brain cells against Parkinsons disease
Does the consumption of green tea, widely touted to have beneficial effects on health, also protect brain cells" Authors of a new study being published in the December 15th issue of Biological Psychiatry share new data that indicates this may be the case. The authors investigated the effects of green tea polyphenols, a group of naturally occurring chemical substances found in plants that have antioxidant properties, in an animal model of Parkinson’s disease.
The authors discovered that green tea polyphenols protect dopamine neurons that increases with the amount consumed. They also show that this protective effect is mediated by inhibition of the ROS-NO pathway, a pathway that may contribute to cell death in Parkinson’s.
Green tea helps beat superbugs
Green tea can help beat superbugs according to Egyptian scientists speaking Monday 31 March 2008 at the Society for General Microbiology’s 162nd meeting being held this week at the Edinburgh International Conference Centre.
The pharmacy researchers have shown that drinking green tea helps the action of important antibiotics in their fight against resistant superbugs, making them up to three times more effective.
Green tea is a very common beverage in Egypt, and it is quite likely that patients will drink green tea while taking antibiotics. The medical researchers wanted to find out if green tea would interfere with the action of the antibiotics, have no effect, or increase the medicines’ effects.
“We tested green tea in combination with antibiotics against 28 disease causing micro-organisms belonging to two different classes,” says Dr Mervat Kassem from the Faculty of Pharmacy at Alexandria University in Egypt. “In every single case green tea enhanced the bacteria-killing activity of the antibiotics. For example the killing effect of chloramphenicol was 99.99% better when taken with green tea than when taken on its own in some circumstances.”
Green tea also made 20% of drug-resistant bacteria susceptible to one of the cephalosporin antibiotics. These are important antibiotics that new drug resistant strains of bacteria have evolved to resist.
The results surprised the researchers, showing that in almost every case and for all types of antibiotics tested, drinking green tea at the same time as taking the medicines seemed to reduce the bacteria’s drug resistance, even in superbug strains, and increase the action of the antibiotics. In some cases, even a low concentration of green tea was effective.
Green Tea Shown to Possess Antitumor Effect in Breast Cancer
A team of scientists have shown that green tea has antitumor effect in breast cancer cells.
Cancer is a disease caused by the increased proliferation of cells which group and form a lump called tumor. Tumors can be benign or malignant. Cells from malignant tumors break away from the original tumor and spread to other parts of the body growing and forming new tumors. They can invade, penetrate into blood and lymphatic vessels, circulate via the bloodstream and can grow in a normal organ or tissue anywhere in the body. Unfortunately treatment options for metastasis are very limited and usually represent the end stage of the disease.
Unlike malignant tumors, benign tumors do not invade and, with very rare exceptions, are not life threatening. Chemoprevention broadly implies the use of a chemical substance of either natural or synthetic origin, to prevent, hamper, arrest or reverse a disease. Phytochemicals are plant based non nutritive components with substantial medicinal properties.
Dr. Maheshwari’s study observed that green tea can inhibit the invading capacity of these breast cancer cells and have also identified the mechanisms involved in death inducing and invasion inhibiting effects of green tea. Epidemiological studies also suggest that the risk of breast cancer is found to be less in Asian countries consuming green tea. These studies have greater clinical significance since the ability of these phytochemicals to activate anti-cancer program of tumor cells might determine the success of chemotherapy.
Ingredient Found In Green Tea Significantly Inhibits Breast Cancer Growth In Female Mice
Green tea is high in the antioxidant EGCG (epigallocatechin-3- gallate) which helps prevent the body’s cells from becoming damaged and prematurely aged. Studies have suggested that the combination of green tea and EGCG may also be beneficial by providing protection against certain types of cancers, including breast cancer. A new study conducted by researchers at the University of Mississippi researchers now finds that consuming EGCG significantly inhibits breast tumor growth in female mice. These results bring us one step closer to better understanding the disease and potentially new and naturally occurring therapies.
Epidemiological studies suggest that green tea and its major constituent, EGCG, can provide some protection against cancer. Because these studies were very limited, the anti-cancer mechanism of green tea and EGCG was not clear. As a result, the researchers examined whether drinking EGCG (just the antioxidant infused in water) inhibited the following: expression of VEGF (vascular endothelial growth factor, which is found in a variety of breast cancer types); tumor angiogenesis (thought to help tumors expand by supplying them with nutrients); and the growth of breast cancer in female mice.
Dr. Gu, the senior researcher for the study, hypothesized that the reason for the link between EGCG and the reductions in the cancer data was because EGCG directly targets both tumor blood vessels and tumor cells of breast cancer for suppressing the new blood vessels formation in breast tumor, the proliferation and migration of breast cancer cells.
Gu concluded by saying, “In this study we have demonstrated that the frequent ingestion of EGCG significantly inhibits breast tumor growth, VEGF expression and tumor angiogenesis in mice. We believe our findings will help lead to new therapies for the prevention and treatment of breast cancer in women.”
Green tea may help lower starchy food blood sugar spikes
Mice fed an antioxidant found in green tea -- epigallocatechin-3-gallate, or EGCG -- and corn starch had a significant reduction in increase in their blood sugar -- blood glucose -- levels compared to mice that were not fed the compound, according to Joshua Lambert, assistant professor of food science in agricultural sciences.
"The spike in blood glucose level is about 50 percent lower than the increase in the blood glucose level of mice that were not fed EGCG," Lambert said.
The dose of EGCG fed to the mice was equivalent to about one and a half cups of green tea for a human.
Lambert, who worked with Sarah C. Forester, postdoctoral fellow, and Yeyi Gu, graduate student, both in food science, said EGCG was most effective when the compound was fed to the mice simultaneously with corn starch. For humans, this may mean that green tea could help them control the typical blood sugar increases that are brought on when they eat starchy foods, like breads and bagels that are often a part of typical breakfasts.
"If what you are eating with your tea has starch in it then you might see that beneficial effect," Lambert said. "So, for example, if you have green tea with your bagel for breakfast, it may reduce the spike in blood glucose levels that you would normally get from that food."
The EGCG had no significant effect on blood sugar spikes in mice that were fed glucose or maltose, according to the researchers who released their findings in the online version of Molecular Nutrition and Food Research. Lambert said that the reason blood sugar spikes are reduced when the mice ate starch, but not these sugars, may be related to the way the body converts starch into sugar.
An enzyme called alpha-amylase that is produced in both the mouth and by the pancreas helps break down starch into maltose and glucose. EGCG may inhibit the enzymes ability to break down the starch, the researchers indicated, since they also found that EGCG reduced the activity of alpha amylase in the pancreas by 34 percent.
If the mechanism holds in humans, this may mean that people who want to limit the blood sugar spike should skip adding sugar to their cup of green tea.
"That may mean that if you add sugar into your green tea, that might negate the effect that the green tea will have on limiting the rise in blood glucose level," Lambert said.
Lambert added that the green tea and the starch would need to be consumed simultaneously. For example, drinking a cup of tea well after eating a piece of toast would probably not change the blood sugar spike.
For the study, researchers separated mice into several groups based on body weight. After a fasting period, the mice were given common corn starch, maltose, or sucrose. One group of mice received EGCG along with the feed, while a control group was not fed the compound.
The researchers then tested the blood sugar levels of both groups.
Lambert said the researchers next step is to test the compound on people.
"The relatively low effective dose of EGCG makes a compelling case for studies in human subjects," the researchers said.
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