Cohort Study of Vitamin C Intake and Cognitive Impairment

Abstract

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.

Nutrition and cognitive impairment in the elderly

“…Many authors suggest vitamin supplementation to enhance nutritional status of elderly people (Chandra et al 1991;Carmel et al 1995;Chandra, 1997;Galan et al 1997;Kelly, 1998;Paleologos et al 1998), especially folic acid, because the costs and risks associated with supplementation of low doses are relatively small in contrast to the benefits. For example, Carmel et al (1995) have proposed supplementation with cobalamin, for although long-standing dementia does not improve, treating such patients with this vitamin could have other concrete benefits.…”

“…However, standard dietary recommendations for healthier lifestyles (e.g. eating more fruit and vegetables) may have the added potential benefits of increasing antioxidant intake and helping to protect cognitive function (Lethem & Orrell, 1997;Paleologos et al 1998).…”

Dietary antioxidant intake and cognitive performance in middle-aged adults

“…A recent report using cross-sectional data from the third National Health and Nutrition Examination Survey indicated a signi®cant association between poor memory and lower serum vitamin E levels, but no association of memory with any other serum antioxidant measured 8 . A small cohort study in Australia showed a signi®cant protective effect of vitamin C intake with one measure of cognitive impairment 9 , but another study in the USA showed no association between use of antioxidant supplements and cognitive function 10 . Recent evidence suggests that antioxidants from diet or vitamin supplements can reduce the risk of cognitive decline associated with ageing.…”

The Relations Between the Vitamins and Alzheimer Dementia

“…In another study investigating the effects of acute, short and long term pre-training administration of ascorbic acid on passive avoidance learning and memory in rats, it was concluded that short-and long-term supplementation with ascorbic acid (vitamin C) had facilitatory effects on acquisition and retrieval processes of passive avoidance learning and memory in rats (Shadidi et al, 2008). Vitamin C supplements were shown to protect against cognitive decline in a 4 year follow up study (Paleologos et al, 1998). In Rotterdam Study (Engelhart et al, 2002), the cohort study of dietary antioxidants with a duration of 6 years, high intakes of vitamin C and E were found to be associated with lower risk of AD.…”