Vitamin C and Other Antioxidant Vitamins Provide No Protection from Cardiovascular Events

In the first large-scale randomized trial of vitamin C on cardiovascular events, researchers at Brigham and Women’s Hospital (BWH) have found that there is no evidence of benefit or risk from vitamins C, E or beta-carotene on cardiovascular events for women at a high risk for cardiovascular disease (CVD). These results are published in the August 13, 2007 issue of Archives of Internal Medicine.

“Consistent with other antioxidant trials, this study shows that vitamins C, E and beta-carotene do not alone, or in combination, increase or decrease the overall risk of cardiovascular events in women at high risk for cardiovascular disease,” said lead author, Nancy Cook, ScD, of the Division of Preventive Medicine at BWH. Most of the earlier studies of antioxidant vitamins had tested only a single vitamin supplement, such as vitamin E alone, and it was unclear whether vitamins in combination would provide greater benefits. In this study, women were randomized to a single vitamin, a combination of vitamins, or to placebo. Researchers followed 8171women who were enrolled in the Women’s Antioxidant Cardiovascular Study (WACS) and were at high risk of cardiovascular disease. Over an average of nine years, women were followed for compliance, side effects and medical events. Researchers found that there was no effect of vitamins C, E or beta-carotene on cardiovascular events in women over 40-yrs-old who were considered at high risk for CVD. Cardiovascular events were classified as heart attack, stroke, coronary bypass surgery or angioplasty, or death from CVD and were confirmed by medical record review. “This research underscores the importance of focusing on proven methods for preventing cardiovascular disease, including physical activity, healthy diet, controlling high blood pressure and high cholesterol, maintaining healthy weight, and avoiding tobacco,” said JoAnn Manson, MD, chief of Preventive Medicine at BWH and principal investigator of WACS.This research was funded by the National Heart Lung and Blood Institute (NHLBI).(Source: Archives of Internal Medicine : Brigham and Women’s Hospital : September 2007)