Antioxidant vitamin supplements aren't beneficial in the prevention of heart disease or stroke, shows a new study.
Researchers have long speculated antioxidant vitamins, such as beta carotene (a form of vitamin A) and vitamin E, might play a role in helping people avoid cardiovascular disease. The vitamins were thought to work by keeping the arteries free of dangerous plaque. Several preclinical studies show supplementing the diet with these vitamins could inhibit plaque build-up in people who have yet to develop any vascular problems. Numerous large studies ensued hoping to confirm that finding.
Investigators decided to review the results of eight large-scale studies involving beta carotene treatment and seven involving vitamin E. All trials included at least 1,000 patients. Patients in the studies were followed between 1.4 years and 12 years. Researchers evaluated whether people who received the active treatments had a lower mortality rate, decreased risk of cardiovascular death, and decreased risk of stroke.
Researchers found vitamin E supplements had no effect on overall mortality or cardiovascular mortality, and they failed to reduce the incidence of stroke. Beta carotene supplements were actually associated with a small but statistically significant increase in overall mortality and cardiovascular mortality.
They recommend people stop taking these supplements.