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the results published in the Archives of Internal Medicine saying that women who took these vitamins on a regular basis experienced a remarkable and statistically significant reduction in stroke risk (31 percent) and heart attack risk (22 percent). The negative results are based on data for all women in the study, but some did not regularly take the vitamins, which negated the overall positive effects, according to newstarget.com, which accused mews outlets of lying to readers that taking vitamins is not effective at preventing cardiovascular events. We reported some positive results at the end of the article for those who can read the article to the end of it. ................................................................ Tuesday August 14, 2007 (Foodconsumer.org) -- Taking antioxidant supplements such as vitamin C and E and beta carotene, either individually or in combination, may not reduce the risk of cardiovascular events in women at high risk for cardiovascular disease (CVD), a new study suggests. The study of 8,171 women age 40 or older found that taking these antioxidant supplements did not reduce risk of heart attacks, strokes, coronary revascularization procedures (bypass surgery or angioplasty) and cardiovascular deaths although they were not associated with any adverse effects either. The trial known as Women's Antioxidant and Cardiovascular Study was conducted by Nancy R. Cook, Sc.D., of Brigham & Women's Hospital and Harvard Medical School, Boston, and colleagues and published in the August 13, 2007 issue of Archive of Internal Medicine. Sponsored by the National Heart, Lung, and Blood Institute, a U.S. government health agency, the trial meant to determine if supplements of vitamin C, vitamin E, beta-carotene, and B-vitamins reduce risk of major cardiovascular events in high risk women with a prior history of atherosclerotic CVD, according to clinicaltrials.gov . The effects of B vitamins including folic acid, vitamin B6, and vitamin B12 were reported early on Nov 13, 2006 at the American Heart Association's Scientific Sessions 2006. The results showed these vitamins did not reduce risk of cardiovascular events. Christine M. Albert, M.D., M.P.H., at Brigham and Women's Hospital in Boston, Massachusetts and colleagues conducted the study. Oxidative damage to cells may attribute to the development of CVD, according to the background information provided by the authors. For example, free radicals formed by oxidations may damage artery linings, encourage blood clots, and alter the function of blood vessels. Early epidemiologic studies have linked diets high in fruit and vegetable intake and thus rich in such supplemental antioxidants as vitamin C, E and beta-carotene to reduced rates of coronary heart disease and stroke. Because antioxidants can scavenge free radicals and limit the oxidative damage to cells, the researchers hypothesized that these antioxidant supplements may have potential same protective effect of a plant-based diet on heart disease. That was what the researchers wanted to prove or disprove. For the trial starting in 1995 and 1996, Cook and colleagues had followed more than 8000 women at an average age of 60.6 years for an average period of 9.4 years. During the follow-up, participants were randomly assigned 500 milligrams of vitamin C supplements or ascorbic acid or placebo every day; 600 international units of vitamin E or placebo every other day; and 50 milligrams of beta carotene or placebo every other day. During the trial, 1,450 women had one or more cardiovascular events, including 274 heart attacks, 298 strokes, 889 coronary revascularization procedures including bypass surgery and angioplasty and 395 cardiovascular deaths out of a total of 995 deaths. "There was no overall effect of ascorbic acid, vitamin E or beta carotene on the primary combined end point or on the individual secondary outcomes of myocardial infarction, stroke, coronary revascularization or cardiovascular disease death," Cook and colleagues write. According to the study report, a marginally significant reduction (11 percent) in the primary outcome with active vitamin E was observed among the pre-specified subgroup of women with prior CVD. Additionally, those randomized to both supplements ascorbic acid and vitamin E experienced fewer strokes. The researchers did not observe any additional adverse effects of taking antioxidant supplements and placebo, with the exception of a small increase in reports of upset stomach among the women taking active beta carotene. "There were no overall effects of ascorbic acid, vitamin E, or beta carotene on cardiovascular events among women at high risk for CVD," the authors conclude. "While additional research into combinations of agents, particularly for stroke, may be of interest, widespread use of these individual agents for cardiovascular protection does not appear warranted." The researchers reported the same negative results on Nov 13, 2006 at the American Heart Association Scientific Sessions 2006. In pre-specified subgroup, women randomized to the vitamin C group and who smoked or who had three or more risk factors but did not have prevalent cardiovascular disease seemed at reduced risk of stroke, the researchers said. They also said those with prior CVD who took vitamin E had a significant reduction in cardiovascular events. A scientist affiliated with foodconsumer.org cautioned that these antioxidant vitamins may not work for women at high risk of heart disease, but their protective effect in other populations who are at low risk of heart disease remains unknown. Additionally, one important factor that remains unknown is what diet and lifestyle those study women followed, meaning that the potential protective effects of these antioxidant vitamins on heart disease and stroke may be negated by unhealthy diet and lifestyle. According to Lynn Greig and Simon Maxwell from the University of Edinburgh who published an article in the Nov 2, 2001 issue of Expert Opinion on Pharmacotherapy, studies in animal models of CVD have suggested that natural and synthetic antioxidants can prevent the development of clinical end points, meaning that antioxidants may also prevent cardiovascular events in humans. The take-home message is that regardless of the effect of antioxidant vitamins on CVD events such as heart attack, stroke, surgery and death; and whether or not antioxidants are effective, consumers should always follow a healthy diet and lifestyle as epidemiologic studies showed certain diets and lifestyle attributes may prevent heart disease. The progression of heart disease in most cases can be halted or reversed simply by following a heart-healthy diet, according to studies by Dr. Dean Ornish, a Harvard-educated physician who promotes plant-based diets for treatment of heart disease. ### Copyright 2007 foodconsumer.org All rights reserved. Foodconsumer.org publishes daily news and reports on food and diet, some of which are not available from the mainstream news media. 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