Tissue Recovery

Eur J Nutr. 2007 Jan 30; [Epub ahead of print]

Prospective study showing that dietary vitamin C reduced the risk of age-related cataracts in a middle-aged Japanese population.

Yoshida M, Takashima Y, Inoue M, Iwasaki M, Otani T, Sasaki S, Tsugane S; for the JPHC Study Group.

Dept. of Pubic Health, Kyorin University School of Medicine, Tokyo, Japan.

In Western countries, many epidemiological studies have demonstrated that specific dietary nutrients are associated with the risk of developing age-related cataracts. These reports have suggested that dietary antioxidant vitamins, in particular vitamin C, can play a role in preventing the onset or progression of age-related visual impairment. However, few prospective studies have examined this relationship in a general Asian population. Therefore, in this study, we investigated whether dietary vitamin C was associated with a lower incidence of age-related cataracts by performing a 5-year prospective population-based analysis using data from a cohort of over 30,000 Japanese residents recruited to the Japan Public Health Center-based Prospective Study (JPHC Study) cohort I. AIM OF THE STUDY: We carried out a prospective analysis of the association between vitamin C intake and age-related cataracts among middle-aged Japanese, to study the effects of dietary antioxidants in an Asian population. METHODS: This 5-year population-based study included 16,415 men and 18,771 women (aged 45-64 years), who were recruited onto the JPHC Study and had not reported cataracts in baseline surveys. Vitamin C was calculated from the nutrient intake assessed by self-administered food-frequency questionnaires (FFQ). Self-reported questionnaires were used to assess two endpoints: diagnosis or extraction of cataracts. RESULTS: At follow-up, 216 men and 551 women reported new diagnoses, and 110 men and 187 women reported extractions of cataracts. For both endpoints, a higher vitamin C intake was associated with a reduced incidence of cataracts in both sexes. After adjusting for potential confounding factors, the multivariate odds ratios (ORs) for men and women in the highest quintiles of energy-adjusted vitamin C intake, relative to the lowest quintiles, were 0.65 (95% CI, 0.42-0.97) and 0.59 (95% CI, 0.43-0.89) for cataract diagnoses, and 0.70 (95% CI, 0.44-1.20) and 0.64 (95% CI, 0.41-0.94) for cataract extractions, respectively. CONCLUSIONS: Dietary vitamin C intake might lower the risk of age-related cataracts among middle-aged Japanese.

PMID: 17265171 [PubMed - as supplied by publisher]