A BRIEF ORIGINAL CONTRIBUTION Cohort Study of Vitamin C Intake and Cognitive Impairment

To test the hypothesis that vitamin C protects against cognitive impairment, the authors conducted a cohort study (n = 117) in a retirement community in Sydney, Australia. Vitamin C intake was assessed at baseline (1991) with a semiquantitative food frequency questionnaire, and cognitive function was assessed 4 years later (1995). After adjustment for age, sex, smoking, education, total energy intake, and use of psychotropic medications, consumption of vitamin C supplements was associated with a lower prevalence of more severe cognitive impairment (based on scores on the Mini-Mental State Examination; adjusted odds ratio = 0.39, 95 % confidence interval 0.18-0.84). There were no associations between vitamin C intake and scores on tests of verbal and category fluency. This study suggests that vitamin C might protect against cognitive impairment. Am J Epidemiol 1998; 148:45-50. Alzheimer's disease; ascorbic acid; cohort studies; cognition; dementia The hypothesis that antioxidant vitamins might pro-tect the brain against Alzheimer's disease has been the subject of much speculation (1-4). Antioxidant vita-mins could also protect against vascular dementia, given recent findings that higher vitamin C intakes ar