Researchers from the Peninsula Medical School, the University of Cambridge and the University of Michigan, have for the first time identified a relationship between Vitamin D, the "sunshine vitamin", and cognitive impairment in a large-scale study of older people. The importance of these findings lies in the connection between cognitive function and dementia: people who have impaired cognitive function are more likely to develop dementia. The paper will appear in a forthcoming issue of the Journal of Geriatric Psychology and Neurology.
The study was based on data on almost 2000 adults aged 65 and over who participated in the Health Survey for England in 2000 and whose levels of cognitive function were assessed. The study found that as levels of Vitamin D went down, levels of cognitive impairment went up. Compared to those with optimum levels of Vitamin D, those with the lowest levels were more than twice as likely to be cognitively impaired.
Obviously this doesn't prove the direction of causation. It could be that cognitively impaired people get outside less in the summer to synthesize vitamin D in their skin in response to UV light. Or cognitively impaired people might eat worse diets.
Other researchers have found a link between low vitamin D and cognitive impairment. Also, a review notes that the brain is rich in vitamin D receptors. Also, some Emory University researchers found that people with Parkinson's Disease have lower blood vitamin D than people with Alzheimer's who, in turn, had lower blood vitamin D than people with neither disease.
|Share |||Randall Parker, 2009 January 23 12:16 AM Aging Diet Brain Studies|