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B Vitamins Protect Heart Patients: The Best Evidence Yet Supplementing with three B vitamins (folic acid, vitamin B6, and vitamin B12) improves clinical outcome in heart patients, according to a report in the Journal of the American Medical Association (2002;288:973–9). Although numerous preliminary studies have suggested that taking these vitamins might promote heart health, this new study is the best designed and most definitive one to date. The implication of the study is that widespread use of an inexpensive and nontoxic vitamin combination could have a major impact in the battle against America's number one killer. Five hundred fifty-three men and women who had undergone a procedure to open one or more blocked coronary arteries (angioplasty) were randomly assigned to receive a placebo or a daily combination of folic acid (1 mg), vitamin B6 (10 mg), and vitamin B12 (400 mcg) for six months. These individuals were observed during the supplementation period and for an additional six months (total observation period, one year). During that time, the proportion of study participants suffering a cardiac event (defined as either death from heart disease, non-fatal heart attack, or need for a repeat angioplasty or bypass operation) was 32% lower in the vitamin group than in the placebo group (15.4% vs. 22.8%; a statistically significant difference). In addition, the incidence of cardiac death was 48% lower in the vitamin group, although the difference between groups was not statistically significant. The protection afforded by these vitamins against heart disease may be due in large part to their capacity to reduce homocysteine levels in the body. Homocysteine is a byproduct of amino acid metabolism that is believed to promote the development of heart disease. It is well established that an elevated blood level of homocysteine is associated with an increased risk of cardiovascular disease. One previous study demonstrated that lowering homocysteine by supplementing with folic acid, vitamin B6, and vitamin B12 can reverse the buildup of plaque in arteries (atherosclerosis). However, the new study is the first to show that taking these vitamins actually improves clinical outcome (i.e., a reduction in adverse cardiac events). While individuals with high homocysteine levels appear to obtain the most benefit from B-vitamin supplementation, these vitamins have also produced regression of atherosclerosis in people with normal homocysteine concentrations. That observation suggests that at least some of the improvement that results from B-vitamin therapy is due to mechanisms other than homocysteine lowering. For example, vitamin B6 has been shown to have a mild blood-thinning effect and to strengthen the walls of arteries; each of these actions would be expected to help prevent or reverse atherosclerosis. Food sources of folic acid, vitamin B6, or both include whole grains, leafy green vegetables, beans, wheat germ, and meat. Vitamin B12 is found almost exclusively in animal foods. Alan R. Gaby, MD, an expert in nutritional therapies, testified to the White House Commission on CAM upon request in December 2001. Dr. Gaby served as a member of the Ad-Hoc Advisory Panel of the National Institutes of Health Office of Alternative Medicine. He is the author of Preventing and Reversing Osteoporosis (Prima, 1994), and co-author of The Natural Pharmacy, 2nd Edition (Healthnotes, Prima, 1999), the A–Z Guide to Drug-Herb-Vitamin Interactions (Healthnotes, Prima, 1999), Clinical Essentials Volume 1 and 2 (Healthnotes, 2000), and The Patient’s Book of Natural Healing (Prima, 1999). A former professor at Bastyr University of Natural Health Sciences, in Kenmore, WA, where he served as the Endowed Professor of Nutrition, Dr. Gaby is the Chief Medical Editor for Healthnotes, Inc. Copyright © 2002 Healthnotes, Inc. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.
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