Health for life

Study shows clear benefits of a healthy diet, exercise, maintaining normal weight and not smoking

A large, multi-center study led by Johns Hopkins researchers has found a significant link between lifestyle factors and heart health, adding even more evidence in support of regular exercise, eating a Mediterranean-style diet, keeping a normal weight and, most importantly, not smoking.

The researchers found that adopting those four lifestyle behaviors protected against coronary heart disease as well as the early buildup of calcium deposits in heart arteries, and reduced the chance of death from all causes by 80 percent over an eight-year period. Results of the study, "Low-Risk Lifestyle, Coronary Calcium, Cardiovascular Events, and Mortality: Results from the Multi-Ethnic Study of Atherosclerosis," are described in an online article posted June 3, 2013 by the American Journal of Epidemiology.

"To our knowledge, this is the first study to find a protective association between low-risk lifestyle factors and early signs of vascular disease, coronary heart disease and death, in a single longitudinal evaluation," says Haitham Ahmed, M.D., M.P.H., the lead author who is an internal medicine resident with the Ciccarone Center for the Prevention of Heart Disease at Johns Hopkins.

"We evaluated data on more than 6,200 men and women, age 44-84, from white, African-American, Hispanic and Chinese backgrounds. All were followed for an average of 7.6 years. Those who adopted all four healthy behaviors had an 80 percent lower death rate over that time period compared to participants with none of the healthy behaviors," says Ahmed.

Study participants all took part in the ongoing Multi-Ethnic Study of Atherosclerosis (MESA), a prospective examination of the risk factors, prevalence and prevention of cardiovascular disease. MESA participants were recruited from six academic medical centers and did not have a diagnosis of cardiovascular disease when they were enrolled.

All participants had coronary calcium screening using computed tomography (a CT scan) when they were first enrolled in the study to see if there were early signs of calcium deposits in their heart arteries that are known to contribute to heart attack risk. As the study progressed, the researchers also assessed whether the participants had a heart attack, sudden cardiac arrest, chest pain, angioplasty or died due to coronary heart disease or other causes.

The researchers developed a lifestyle score for each of the participants, ranging from 0 (least healthy) to 4 (healthiest), based on their diet, body mass index (BMI), amount of regular moderate-intensity physical activity and smoking status. Only 2 percent, or 129 participants, satisfied all four healthy lifestyle criteria.

"Of all the lifestyle factors, we found that smoking avoidance played the largest role in reducing the risk of coronary heart disease and mortality," says Roger Blumenthal, M.D., a cardiologist and professor of medicine at the Johns Hopkins University School of Medicine, director of the Ciccarone Center and senior author of the study. "In fact, smokers who adopted two or more of the healthy behaviors still had lower survival rates after 7.6 years than did nonsmokers who were sedentary and obese."

Blumenthal, who is also the president of the American Heart Associations Maryland affiliate, says the findings "bolster recent recommendations by the American Heart Association, which call for maintaining a diet rich in vegetables, fruits, nuts, whole grains and fish, keeping a BMI of less than 25, being physically active and not smoking."

The researchers emphasize that their study shows the importance of healthy lifestyle habits not just for reducing the risk of heart disease, but also for preventing mortality from all causes.

"While there are risk factors that people cant control, such as their family history and age," says Ahmed, "these lifestyle measures are things that people can change and consequently make a big difference in their health. Thats why we think this is so important."

Statin use is associated with protection from esophagus cancer according to a new meta-analysis of existing clinical studies exploring the cancer prevention effects of statins presented by a Mayo Clinic researcher, Dr. Siddharth Singh, at the American College of Gastroenterology 77th Annual Scientific Meeting in Las Vegas, NV.

Dr. Singh and his Mayo colleagues conducted a systematic review of eleven studies reporting 8,613 cases of esophageal cancer from studies including almost 1 million patients. Incidence of esophageal cancer is increasing in the United States, especially esophageal adenocarcinoma in patients with Barretts esophagus.

"The meta-analysis of these studies showed a significant 30 percent reduction in esophageal cancer incidence with statins use," said Dr. Singh.

When looking more closely at the seven highest-quality observational studies among the eleven, researchers continued to find a significant chemo-protective effect with statin use. An analysis of a subset of patients with Barretts esophagus, a pre-malignant condition associated with chronic acid lux, revealed that, in this higher risk population, statin use was associated with a significant 41 percent decrease in the risk of adenocarcinoma of the esophagus.

Swedish researchers at the Sahlgrenska Academy, University of Gothenburg, Sweden, report that a simple habit may give significant protection against allergy development, namely, the parental sucking on the babys pacifier.

Allergies are very common in industrialized countries. It has been suggested that exposure to harmless bacteria during infancy may be protective against the development of allergy. However, it has been difficult to pinpoint which bacteria a baby should be exposed to, and at what time and by which route this exposure should ideally occur.

Swedish researchers at the Sahlgrenska Academy, University of Gothenburg, now report that a simple habit may give significant protection against allergy development, namely, the parental sucking on the babys pacifier.

In a group of 184 children, who were followed from birth, the researchers registered how many infants used a pacifier in the first 6 months of life and how the parents cleaned the pacifier. Most parents rinsed the pacifier in tap water before giving it to the baby, e.g., after it had fallen on the floor. However, some parents also boiled the pacifier to clean it. Yet other parents had the habit of putting the babys pacifier into their mouth and cleaning it by sucking, before returning it to the baby.

It was found that children whose parents habitually sucked the pacifier were three times less likely to suffer from eczema at 1.5 years of age, as compared with the children of parents who did not do this. When controlled for other factors that could affect the risk of developing allergy, such as allergy in the parents and delivery by Caesarean section, the beneficial effect of parental sucking on the pacifier remained.

Pacifier use per se had no effect on allergy development in the child. Boiling the pacifier also did not affect allergy development in a statistically proven fashion.

No more upper respiratory infections were seen in the children whose parents sucked on their dummies, as compared with the other children, as evidenced by diaries kept by the parents in which they noted significant events, such as infections.

Saliva is a very rich source of bacteria and viruses, and the researchers believe that oral commensal microbes are transferred from parent to infant when they suck on the same pacifier. When the composition of the bacterial flora in the mouth was compared between infants whose parents sucked on their pacifiers and those whose parent did not, it was found to differ, supporting this hypothesis.

According to "the hygiene hypothesis", the development of allergy can be attributed in part to a paucity of microbial stimulation during early infancy.

"Early establishment of a complex oral microflora might promote healthy maturation of the immune system, thereby counteracting allergy development", says professor Agnes Wold who led the study.

The study, which is published in the scientific journal Pediatrics, was performed by a team that consisted of paediatricians specialized in allergic diseases, as well as microbiologists and immunologists. The research team has previously conducted large-scale studies on the gut microbiota in relation to allergy development and showed in 2009 that a complex gut microbiota very early in life reduces the risk of allergy development.

According to the 2005 CDC report, National Diabetes Fact Sheet (US Centers for Disease Control and Prevention):

"About one in every 400 to 600 children and adolescents has type 1 diabetes."

Thats a lot of children.

To answer the question I posed in my title, a group of researchers in the UK conducted a meta-analysis (a study of studies) of five observational studies that investigated the effect of vitamin D supplementation on the risk of developing type 1 diabetes.¹ Their findings were reported last week in the online edition of the Archives of Disease in Childhood:

"Meta-analysis of data ... showed that the risk of type 1 diabetes was significantly reduced in infants who were supplemented with vitamin D compared to those who were not supplemented."

And ...

"There was also some evidence of a dose-response effect, with those using higher amounts of vitamin D being at lower risk of developing type 1 diabetes."

Unlike the more common type 2 diabetes, type 1 is an auto-immune disease. It develops when the bodys immune system destroys pancreatic beta cells. Beta cells produce the hormone insulin which regulates blood glucose. Without insulin, diabetes results.

Both pancreatic beta cells and immune system cells carry receptors for vitamin D. Future research may shed light on how the vitamin operates among these cells.
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¹ Vitamin D Supplementation in Early Childhood and Risk of Type 1 Diabetes: a Systematic Review and Meta-analysis

News summary, BBC:
Vitamin D Cuts Risk of Diabetes

New research shows that a Mediterranean-style diet and diets low in available carbohydrates can offer protection against type 2 diabetes. The study is published in Diabetologia, the journal of the European Association for the Study of Diabetes (EASD), and is by Dr Carlo La Vecchia, Mario Negri Institute of Pharmacological Research, Milan, Italy, and colleagues.

The authors studied patients from Greece who are part of the ongoing European Prospective Investigation into Cancer and nutrition (EPIC), led by Dr. Antonia Trichopoulou, from the University of Athens. From a total of 22,295 participants, actively followed up for just over 11 years, 2,330 cases of type 2 diabetes were recorded. To assess dietary habits, all participants completed a questionnaire, and the researchers constructed a 10-point Mediterranean diet score (MDS) and a similar scale to measure the available carbohydrate (or glycaemic load [GL]) of the diet.

People with an MDS of over 6 were 12% less likely to develop diabetes than those with the lowest MDS of 3 or under. Patients with the highest available carbohydrate in their diet were 21% more likely to develop diabetes than those with the lowest. A high MDS combined with low available carbohydrate reduced the chances of developing diabetes by 20% as compared with a diet low in MDS and high in GL.

The authors say: "The role of the Mediterranean diet in weight control is still controversial, and in most studies from Mediterranean countries the adherence to the Mediterranean diet was unrelated to overweight. This suggests that the protection of the Mediterranean diet against diabetes is not through weight control, but through several dietary characteristics of the Mediterranean diet. However, this issue is difficult to address in cohort studies because of the lack of information on weight changes during follow-up that are rarely recorded."

They point out that a particular feature of the Mediterranean diet is the use of extra virgin olive oil which leads to a high ratio of monounsaturated to saturated fatty acids. But again research here has been conflicting. One review of dietary fat and diabetes suggests that replacing saturated and trans fats with unsaturated fats has beneficial effects on insulin sensitivity and is likely to reduce the risk of type 2 diabetes. However, in a randomised trial of high-cardiovascular-risk individuals who were assigned to the Mediterranean diet supplemented with either free extra virgin olive oil or nuts and were compared with individuals on a low-fat diet (comparison group), there was no difference in diabetes occurrence between the two variants of the Mediterranean diet when compared with the comparison group.

Regarding GL, the authors say: "High GL diet leads to rapid rises in blood glucose and insulin levels. The chronically increased insulin demand may eventually result in pancreatic β cell failure and, as a consequence, impaired glucose tolerance and increased insulin resistance, which is a predictor of diabetes. A high dietary GL has also been unfavourably related to glycaemic control in individuals with diabetes."

They conclude: "A low GL diet that also adequately adheres to the principles of the traditional Mediterranean diet may reduce the incidence of type 2 diabetes.

(Article first published as Acai and the Berry Family Promote Health for the New Year on Technorati.)
Each day our cells are bombarded with negatively charged ions known as free radicals that cause damage leading to accelerated aging and increased risk of heart disease, cancer and dementia. It`s estimated that each of our trillion or so cells is assaulted by up to 10,000 free radicals each day.

Medical researchers from the Yale-Griffin Prevention Research Center in Connecticut have found evidence suggestive that adding walnuts to ones diet can protect against diabetes and heart disease in at-risk individuals. Their original research article, "Effects of Walnuts on Endothelial Function in Overweight Adults with Visceral Obesity: A Randomized, Controlled, Crossover Trial," is now available in the Journal of the American College of Nutrition, the Official Publication of the American College of Nutrition, and a publication from Routledge.

For the study, a sample of 46 adults aged 30-75 were selected. Participants had a Body Mass Index larger than 25, and a waist circumference exceeding 40 inches for men and 35 inches for women. They were also required to be non-smokers, and all exhibited one or more additional risk factors for metabolic syndrome, a precursor of diabetes and cardiovascular disease. The group was randomly assigned to two 8-week sequences of either a walnut-enriched ad libitum diet or an ad libitum diet without walnuts. Those chosen for the walnut diet were instructed to consume 56g of shelled, unroasted English walnuts per day as a snack or with a meal.

"We know that improving diets tends to be hard, but adding a single food is easy," explained Dr. David Katz, Director of the Yale-Griffin Prevention Research Center and lead author of the research team. "Our theory is that if a highly nutritious, satiating food like walnuts is added to the diet, there are dual benefits: the benefits of that nutrient rich addition and removal of the less nutritious foods."

The research found that daily intake of 56g of walnuts improves endothelial function in overweight adults with visceral adiposity. The addition of walnuts to the diet does not lead to weight gain. Further study on the topic is still suggested. "The primary outcome measure was the change in flow-mediated vasodilatation (FMD) of the brachial artery," wrote the research group. "Secondary measures included serum lipid panel, fasting glucose and insulin, Homeostasis Model Assessment-Insulin Resistance values, blood pressure, and anthropometric measures. FMD improved significantly from baseline when subjects consumed a walnut-enriched diet as compared with the control diet. Beneficial trends in systolic blood pressure reduction were seen, and maintenance of the baseline anthropometric values was also observed. Other measures were unaltered."

"Use it or lose it." The saying could apply especially to the brain when it comes to protecting against Alzheimers disease. Previous studies have shown that keeping the mind active, exercising and social interactions may help delay the onset of dementia in Alzheimers disease.

Now, a new study led by Dennis Selkoe, MD, co-director of the Center for Neurologic Diseases in the BWH Department of Neurology, provides specific pre-clinical scientific evidence supporting the concept that prolonged and intensive stimulation by an enriched environment, especially regular exposure to new activities, may have beneficial effects in delaying one of the key negative factors in Alzheimers disease.

The study will be published online on March 6, 2013 in Neuron.

Alzheimers disease occurs when a protein called amyloid beta accumulates and forms "senile plaques" in the brain. This protein accumulation can block nerve cells in the brain from properly communicating with one another. This may gradually lead to an erosion of a persons mental processes, such as memory, attention, and the ability to learn, understand and process information.

The BWH researchers used a wild-type mouse model when evaluating how the environment might affect Alzheimers disease. Unlike other pre-clinical models used in Alzheimers disease research, wild-type mice tend to more closely mimic the scenario of average humans developing the disease under normal environmental conditions, rather than being strongly genetically pre-disposed to the disease.

Selkoe and his team found that prolonged exposure to an enriched environment activated certain adrenalin-related brain receptors which triggered a signaling pathway that prevented amyloid beta protein from weakening the communication between nerve cells in the brains "memory center," the hippocampus. The hippocampus plays an important role in both short- and long-term memory.

The ability of an enriched, novel environment to prevent amyloid beta protein from affecting the signaling strength and communication between nerve cells was seen in both young and middle-aged wild-type mice.

"This part of our work suggests that prolonged exposure to a richer, more novel environment beginning even in middle age might help protect the hippocampus from the bad effects of amyloid beta, which builds up to toxic levels in one hundred percent of Alzheimer patients," said Selkoe.

Moreover, the scientists found that exposing the brain to novel activities in particular provided greater protection against Alzheimers disease than did just aerobic exercise. According to the researchers, this observation may be due to stimulation that occurred not only physically, but also mentally, when the mice moved quickly from one novel object to another.

"This work helps provide a molecular mechanism for why a richer environment can help lessen the memory-eroding effects of the build-up of amyloid beta protein with age," said Selkoe. "They point to basic scientific reasons for the apparent lessening of AD risk in people with cognitively richer and more complex experiences during life."

A Loyola University Chicago Stritch School of Medicine study suggests that omega-3 fish oil might help protect against alcohol-related dementia.

Previous studies have shown that long-term alcohol abuse increases the risk of dementia. The Loyola study found that in the brain cells of rats exposed to high levels of alcohol, a fish oil compound protected against inflammation and cell death.

The study by Michael A. Collins, PhD, and colleagues was reported Sept. 8 at the 14th Congress of the European Society for Biomedical Research on Alcoholism in Warsaw.

An earlier analysis by Collins and Loyola colleague Edward J. Neafsey, PhD, which pooled the results of 143 studies, found that moderate social drinking may reduce the risk of dementia and cognitive impairment. (Moderate drinking is defined as a maximum of two drinks per day for men and 1 drink per day for women.)

It appears that small amounts of alcohol might, in effect, make brain cells more fit. Alcohol in moderate amounts stresses cells and thus toughens them up to cope with major stresses down the road that could cause dementia. But too much alcohol overwhelms the cells, leading to inflammation and cell death.

In the new study, Collins and colleagues exposed cultures of adult rat brain cells to amounts of alcohol equivalent to more than four times the legal limit for driving. These cell cultures were compared with cultures of brain cells exposed to the same high levels of alcohol, plus a compound found in fish oil called omega-3 docosahexaenoic acid (DHA).

Researchers found there was about 90 percent less neuroinflammation and neuronal death in the brain cells exposed to DHA and alcohol than in the cells exposed to alcohol alone.

Further studies are needed to confirm whether fish oil protects against alcohol-related dementia. "Fish oil has the potential of helping preserve brain integrity in abusers," Collins said. "At the very least, it wouldnt hurt them."

But Collins added that best way for an alcohol abuser to protect the brain is, if possible, to quit drinking or cut back to moderate amounts. "We dont want people to think its okay to take a few fish oil capsules and then continue to go on abusing alcohol."

Health conscious individuals would cite vitamin E as an essential antioxidant necessary for cardiovascular health and protection from cancer. There are a number of different tocopherol forms of vitamin E known as isomers and it’s important to understand that both the alpha and gamma types must be available in the body to lower risk from disease.