What have studies found about the effect of antioxidant vitamins on cardiovascular risk?
Epidemiological and population studies have suggested that antioxidant vitamins, such as vitamin E, vitamin C, and beta-carotene, could lower cardiovascular risk. However, controlled clinical trials have failed to demonstrate a beneficial effect of antioxidant supplements on risk of cardiovascular morbidity and mortality. A meta-analysis of antioxidant vitamin studies found that vitamin E had no effect on all-cause mortality or cardiovascular death, while beta-carotene led to a small but statistically significant increase in all-cause mortality and cardiovascular death. Thus, existing scientific evidence does not justify routine use of antioxidant supplements for the prevention or treatment of cardiovascular disease.