Vitamin C and E supplements do not appear to prevent dementia, including dementia caused by Alzheimer's disease, according to a report in the Journal of the American Medical Association.

Researchers at the National Institute of Aging report that vitamin C and E, taken separately or in combination, do not change one's risk of developing dementia.

Prior studies have suggested that the formation of free radicals could be linked to the development of Alzheimer's disease and vascular dementia, and that the antioxidants vitamins C and E could have a beneficial effect on this process.

In the Honolulu-Asia Aging Study, researchers asked 2,369 men about their use of vitamin supplements. Two different assessments were conducted to identify cases of dementia in these men. The average follow-up period was 5.2 years.

Compared with the control group, men using both vitamin E and vitamin C (either for long or short term) were not at reduced risk for dementia including Alzheimer's disease, Alzheimer's disease with contributing cerebrovascular disease or vascular dementia. Also, no links were found for supplements taken separately.

Other sources: Journal of the American Medical Association