Results of several clinical trials indicated that beta-carotene supplementation is not beneficial in the prevention of cardiovascular disease or its complications.
1. The Carotene and Retinol Efficacy Trial (CARET) trial included 8314 men and women with a history of cigarette smoking or occupational exposure to asbestos receiving beta-carotene (30 mg per day), and retinol (25,000 IU per day). This trial was stopped early because the incidence of mortality from lung cancer was excessive. However, the population studied in these trials was already at high risk for lung cancer.
2. The physician’s health study randomized 22071 male physicians taking beta-carotene (50 mg per day), aspirin 325 mg, both, or neither for 12 years. There were no cardiovascular benefits from beta-carotene administration. 3. In the Alpha Tocopherol Beta-Carotene Cancer Preven¬tion Trial (ATBC) the effects of daily doses of 50 IU of vitamin E, 20 mg of beta-carotene, both, or placebo for 5 to 8 years in 29133 smokers with a previous myocardial infarct were monitored. The study found no reduction in risk for major coronary events with any of the antioxidants.