Long-term antioxidant supplementation has no effect on health-related quality of life: the randomized, double-blind, placebo-controlled, primary prevention SU.VI.MAX trial.

Background: The effect of antioxidant vitamin and mineral supplementation on health is one of the most controversial issues in human nutrition. Our objective was to investigate the effect of nutritional doses of a combination of antioxidant vitamins and minerals on health-related quality of life (HRQoL) in a sample of healthy French adults.

Methods: SU.VI.MAX is a randomized, double-blind, placebo-controlled, primary prevention trial in which a total of 8112 participants received a single capsule daily containing either placebo or vitamin C 120 mg, vitamin E 30 mg, beta-carotene 6 mg, selenium 100 μg and zinc 20 mg. Participants completed HRQoL questionnaires (SF36 and GHQ12) at baseline and after a mean of 76.0 ± 4.2 months.

Results: Scores for physical dimensions tended to decrease over time, whereas those for mental dimensions tended to improve. No differences in changes over time were observed between the supplement and placebo groups. Participants who believed that they received placebo had lower HRQoL scores than did those who thought they had received supplements [SF36 Bodily pain (-3.3), General health (-2.2), Vitality (-1.6) dimensions and physical component summary score (-1.1) in men, and in SF36 Social functioning (-2.3), General health (-1.4) dimensions and physical component summary score (-0.7) in women].

Conclusions: Long-term supplementation with antioxidant vitamins and minerals had no beneficial effect on HRQoL in this trial. This is contrary to conventional beliefs and claims that such an effect exists. Trial Registration "Primary Prevention Trial of the Health Effects of Antioxidant Vitamins and Minerals." NTC n 00272428 http://www.clinicaltrials.gov.