Dietary supplementation with antioxidants. Is there a case for exceeding the recommended dietary allowance?

The containment of damaging oxygen species by antioxidant nutrients has led to the speculation that the RDA for these specific nutrients may be overly low. Among these nutrients are vitamin E, vitamin C, and to a lesser extent beta-carotene and selenium. Evidence for the role of these nutrients in cancer and heart disease is evaluated. The case is presented for an increase of two-fold for the vitamin C RDA and between three and five-fold for vitamin E; for establishing 15 mg as the RDA for beta-carotene; for no change in the vitamin A RDA; and for further study on selenium.