To assess the relation between usual nutrient intake and subsequently diagnosed age-related nuclear lens opacities.
Four hundred seventy-eight nondiabetic women aged 53 to 73 years from the Boston, Mass, area without previously diagnosed cataracts sampled from the Nurses' Health Study cohort.
Usual nutrient intake was calculated as the average intake from 5 food frequency questionnaires that were collected during a 13- to 15-year period before the evaluation of lens opacities. The duration of vitamin supplement use was determined from 7 questionnaires collected during this same period. We defined nuclear opacities as a nuclear opalescence grade of 2.5 or higher using the Lens Opacification Classification System III.
The prevalence of nuclear opacification was significantly lower in the highest nutrient intake quintile category relative to the lowest quintile category for vitamin C (P<.001), vitamin E (P = .02), riboflavin (P = .005), folate (P = .009), β-carotene (P = .04), and lutein/zeaxanthin (P = .03). After adjustment for other nutrients, only vitamin C intake remained significantly associated (P = .003 for trend) with the prevalence of nuclear opacities. The prevalence of nuclear opacities was significantly lower (P<.001) in the highest vitamin C intake quintile category relative to the lowest quintile category (odds ratio, 0.31; 95% confidence interval, 0.16-0.58). There were also statistically significant trends of decreasing prevalence of nuclear opacities with increasing duration of use of vitamin C (P = .004 for trend), vitamin E (P = .03 for trend), and multivitamin (P = .04 for trend) supplements, but only duration of vitamin C supplement use remained significantly associated with nuclear opacities after mutual adjustment for use of vitamin E (P = .05 for trend) or multivitamin (P = .02 for trend) supplements. The prevalence of nuclear opacities was significantly lower (P = .004) for women who used a vitamin C supplement for 10 or more years relative to women who never used vitamin C supplements (odds ratio, 0.36; 95% confidence interval, 0.18-0.72). Plasma measures of vitamins C and E taken at the eye examination were also inversely associated with the prevalence of nuclear opacities.
These results provide additional evidence that antioxidant nutrients play a role in the prevention of age-related nuclear lens opacities.