Food and Health Communications

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Vitamin E Follows Beta Carotene

Back in 1996, two very well publicized epidemiological studies from well-respected Harvard researchers found a significant correlation between vitamin E intake and a more favorable cardiovascular risk profile.1, 2 This is similar to the favorable reports with higher beta-carotene levels being associated with a decreased risk of some forms of cancer. Unfortunately, when beta-carotene supplements were tested in a prospective trial it was found to increase the risk of cancer and also significantly increase the overall risk of dying.Prospective clinical trials with vitamin E have been a bit more hopeful than beta-carotene. In one well-designed study, vitamin E supplements were associated with a reduced risk of non-fatal heart attacks. However, this same study showed an increase in overall mortality in those taking vitamin E.3 In January, a randomised, placebo controlled clinical trial examined the impact of 400 IU supplement of vitamin E (from natural sources) on the risk of cardiovascular disease in older people (55y+) who were at high risk for CVD. After 4 1/2 years, 16.2% of those taking vitamin E suffered a major cardiovascular event compared to 15.5% of those taking the placebo. Overall mortality was slightly, but not significantly, higher in those taking vitamin E than a placebo.4The results of this study are clearly disappointing to those who would like to believe that taking dietary supplements such as vitamin E is a safe and effective way to reduce deaths from CVD. They can perhaps take solace in the fact that at least those taking the vitamin E did not experience a significant increase in either CVD or overall mortality as was demonstrated for beta-carotene supplements. Nevertheless, this study did show increased deaths from strokes in those taking vitamin E supplements compared to those taking the placebo (209 vs 180). While the higher stroke rate in this study was not quite statistically significant, there is reason to suspect that high doses of vitamin E could increase the risk of hemorrhagic strokes, particularly in those with high blood pressure. This study showed vitamin E supplements were not beneficial for older people at risk for cardiovascular disease.References:1. Rimm EB N Engl J Med 1996;328:1450-62. Stampher MJ N Engl J Med 1996;328:1444-93. Stephens NG Lancet 1996;347:781-64. Yusuf  S N Engl J Med2000; 342:154-60