Antioxidant vitamin supplementation in cardiovascular diseases

Cardiovascular disease is the most important adult health problem in wealthy countries, where biological factors such as obesity, hypertension, dyslipidemia, diabetes, inappropriate diet, cigarette smoking, and sedentary life-style have contributed to its dissemination. Research concerning nutritional regimens has shown that persons who consume large amounts of fruit and vegetables have lower incidences of cardiovascular diseases, stroke, and tumors, although the precise mechanisms for this protective effect are elusive. Possible explanations include (a) increased consumption of dietary fiber, (b) reduced consumption of dietary cholesterol and other lipids, and (c) increased intake of the antioxidant vitamins (A, C, and E). Numerous studies have raised the question whether vitamin supplements help to prevent cardiovascular diseases. Results of randomized controlled trials of antioxidant vitamin supplements in large numbers of participants has been ambiguous or contradictory. This minireview examines the relevant clinical reports on dietary supplements of vitamins A, C, and E to determine whether they support the premise that patients at risk of cardiovascular disease may be candidates for this therapeutic option.