Do Low Vitamin D Levels Impair Thinking?
May 29, 2009

A study in the Journal of Neurology, Neurosurgery, and Psychiatry found that low vitamin D levels in the body are associated with cognitive (thinking) impairments in older men who were enrolled in the European Male Aging Study (EMAS)..

The study looked at 3133 European men, aged 40 to 79 years of age. Dr. David M. Lee, from the University of Manchester, UK, and co-researchers found that the men with the lowest vitamin D levels scored worse in a standard test of cognitive ability than men with normal levels. Although, the authors emphasize, the difference in scores was not that great.

The average level of 25-hydroxyvitamin D, an blood measurement for vitamin D was 63 nanomoles per liter. Levels of 90 to 140 nanomoles per liter are typically considered optimal.

The effect that vitamin D appears to have was largely confined to men over age 60 and was strongest with vitamin D levels below 35 nanomoles per liter.

Dr. Lee and colleagues note that if a simple measure, such as vitamin D supplementation, could improve cognition, the findings could have important public health implications.

Journal of Neurology, Neurosurgery, and Psychiatry, May 21, 2009 online issue.