Fig. 8. Cataract risk ratio, high versus low intake (with or without supplements) for plasma levels of carotenoids (generally measured as β-carotene). (Adapted from Taylor A, Dorey CK, Nowell T Jr. Oxidative stress and ascorbate in relation to risk for cataract and age-related maculopathy. In Packer L, Fuchs J [eds]: Vitamin C in Health and Disease. New York: Marcel Dekker, 1997.)