The SU.VI.MAX Study

Abstract

Experimental studies have demonstrated that free radicals can induce numerous pathological processes, and it has been suggested that nutrients such as beta carotene, ascorbic acid, vitamin E, selenium, and zinc may prevent such harmful effects because of their antioxidant capacity.^1-3 Epidemiological data from cross-sectional, case-control, and prospective studies have indeed shown a strong relationship between the intake of antioxidant vitamins and minerals, or of foods rich in these nutrients, and the risks of cancer and ischemic cardiovascular disease (CVD).^4-8 However, randomized, placebo-controlled, primary prevention trials in which antioxidant micronutrients, single or in pairs, were taken at high doses over long periods have not confirmed this potential beneficial effect,^9-14 and 2 of these^10,11 even suggested harmful effects. The seemingly contradictory results between the observational studies and these randomized trials can be explained by the fact that the doses used in clinical trials were much higher than the highest levels found in ordinary dietary intake—levels associated with the lowest risk of cancer and CVD. In fact, the only trial that observed a beneficial effect on total mortality and cancer incidence used nutritional doses of a combination of several vitamins and minerals and was performed on a Chinese population with very low baseline micronutrient status because of poor life conditions.⁹