Healthy Heart Beats

January-March 2009
Vol 31, Issue 1

Nutrition and Research Updates

Vitamin E and C Supplementation and
Cardiovascular Disease in Men

Vitamin E and C Vitamin supplement sales are a billion dollar industry and most U.S. adults report taking a vitamin supplement in the past year. Single nutrients, such as vitamins E and C, are popular as well due to their purported cardiovascular disease-reducing properties. The use of supplements is a growing public health concern and research is beginning to explore their true potential and value to health.

The Physicians' Health Study II was a randomized, double-blind, placebo-controlled trial that examined 14,641 U.S. male physicians on the effects of vitamins E and C in the prevention of cardiovascular disease in men. All subjects were 50 years or older and included 754 men with cardiovascular disease at randomization. As part of the intervention subjects were given supplements of 400 IU of vitamin E every other day and 500 mg of vitamin C daily. The study began in 1997 with a mean follow-up of eight years.

Compared with placebo neither vitamins E nor C had a significant effect on major cardiovascular events, including total myocardial infarction, total stroke, and cardiovascular mortality. Further, no benefit for vitamin E or C supplementation was found for those with cardiovascular disease or family history of cardiovascular disease. Additionally, neither vitamin E nor vitamin C had a significant effect on total mortality, but vitamin E was associated with an increased risk of hemorrhagic stroke.

This large, long-term trial provides no support for the use of vitamin E or C supplements in the prevention of cardiovascular disease in men. This is not to say, however, that consumption of foods rich in these nutrients is not encouraged. Single nutrients in supplement form act differently than those found in food, where a variety of complex interactions occur. The conclusions of the study do not negate the antioxidant properties of vitamins E and C, but suggest that supplement form is not helpful in the prevention of cardiovascular disease.

Source: Journal of the American Medical Association, 2008, 300(18): 2123-2133 (November).

Committee Appointed to Review Vitamin D Supplementation

The Institute of Medicine (IOM) has announced the composition of the next vitamin D committee of the Food and Nutrition Board (FNB), a committee that will set recommendations for both adequate intake and upper limits. To view project information and a list of members along with their background and expertise, go to http://www8.nationalacademies.org/cp/committeeview.aspx?key=49031.

Lower Sodium Intake and Increase Potassium
to Combat Heart Disease

The trials of hypertension prevention (TOHP) I and II evaluated the effects of sodium reduction and other interventions on the risk of cardiovascular disease (CVD). "The totality of evidence suggests that lowering dietary sodium intake, while increasing potassium consumption, at the population level might reduce the incidence of CVD," concluded the researchers.

potassium and sodium Data was based on the results of urine samples collected from the follow-up information of 2,275 participants with pre-hypertension over intermittent 24-hour periods. TOHP I looked at the relationship with life-style interventions of weight loss, sodium reduction, and stress management, and supplements of calcium, magnesium, potassium, and fish oil over eighteen months. TOHP II tested the effect of weight loss and sodium reduction over a three year period.

Harvard researchers reported that when the sodium to potassium excretion ratio was higher the risk of CVD increased by 24 percent. The study suggests those with pre-hypertension should increase potassium consumption along with the current guideline to lower salt intake to reverse the risk of CVD.

Source: Archives of Internal Medicine, 2009, 169(1): 32-40 (January).

Eat Soy for Complete Source of Protein

Soybeans are a complete protein containing all the essential amino acids required for human nutrition. The recommendation for dietary whole soy protein is 25 grams per day. Increasing dietary whole soy protein lowers lipid levels of total cholesterol, low-density lipoproteins, and triglycerides. Soy intake may improve menopausal hot flashes and may help maintain bone health and decrease fractures in postmenopausal women. However, there is no indication soy is effective for cancer prevention. Examples of foods that contain soy include: edamame, tofu, soy milk, soy flour, tempeh, miso and soy sauce. Supplements containing soy isoflavone have not shown the same health effects as consuming dietary whole soy protein. There are no contraindications for adding soy to the diet. The greatest advantage is that soy can be substituted for higher-fat animal products while lowering lipid levels.

Source: American Family Physician, 2009, 79(1): 43-47 (January).

Switching to the Mediterranean Diet
Insures Ample Fruits and Vegetables

Two specific characteristics of a Mediterranean dietary pattern are high consumption of fruits and vegetables and a high intake of monounsaturated fat. In this randomized study 69 women were divided into two groups. One group followed their usual diet for six months. The other group used an "exchange list" developed specifically for the Mediterranean Diet by registered dietitians. Each participant in the intervention group maintained her original total calorie and fat intake upon entering the study. Dietitians provided both individual counseling sessions as well as support by telephone to the intervention group.

Researchers found that the group who followed the exchange-list plan reached the goals of the Mediterranean dietary pattern within three months, and maintained the change for the six-month duration of the study. Fruit and vegetable intake increased from 4.0 to 8.6 servings per day. Monounsaturated fat intake increased to a statistically significant level of 48 percent without change in total fat intake. However, the group following their usual diet without benefit of the exchange lists or counseling made few dietary changes.

"That tells us that the exchange list was helpful in assisting women to make major changes in their diet, without changes in their caloric or total fat intake," says lead author Zora Djuric, Ph.D., research professor of Family Medicine at the University of Michigan Medical School.

Source: Journal of the American Dietetic Association, 2008, 108 (12): 2059-2065 (December).

Tainted Weight Loss Products
Flagged as Health Risks

weight loss On December 22, 2008, the Food and Drug Administration (FDA) alerted consumers not to buy or use more than 25 different weight-loss pill products because the products may be harmful to health. Anyone using any of these weight-loss products should be advised to stop taking them and consult a health care professional immediately. Visit this Web site www.fda.gov/bbs/topics/NEWS/2008/NEW01933.html for more specific information including:

Which products have been cited
Why the FDA acted against these products
What undeclared ingredients were found
Where these products are sold
What steps the FDA is taking

Consumers should:

Be advised to seek guidance from a health care professional before purchasing weight-loss products.
Report serious adverse reactions or product quality problems to FDA's MedWatch Adverse Event Reporting program at www.fda.gov/MedWatch/report.htm.
Get more information at www.fda.gov/cder/consumerinfo/weight_loss_products.htm.

Omega-6 Fatty Acids Heart Healthy

Vegetable oils, nuts and seeds are plentiful in omega-6 fatty acids and are a beneficial part of a heart-healthy eating plan, according to a science advisory published in the January 27, 2009, edition of Circulation: Journal of the American Heart Association. View the full Omega-6 Advisory here.

Source: American Heart Asssociation News Release. Omega-6 fatty acids: Make them a part of heart-healthy eating DALLAS, Jan. 27, 2009.