Dementia is a hot topic these days with the aging baby boomers. Lots of articles online talk about how to prevent dementia. One of the things they all say is to be outside. Why? Because of vitamin D.

Vitamin D stimulates macrophage activity that clears amyloid plaques through phagocytosis. Vitamin D also reduces amyloid-induced cytotoxicity and apoptosis in primary cortical neurons. Vitamin D deficiency has also been linked to vascular dysfunction, ischemic stroke, and brain atrophy.

Studies have been made in the past that have linked low vitamin D levels with cognitive decline. However, across all the studies there have been some discrepancies with the findings and whether vitamin D deficiency is linked with Alzheimer’s or non-Alzheimer’s dementia. This study set out to find out once and for all.

In this study, researchers followed 1,658 elderly people without dementia, cardiovascular disease and stroke for 5.6 years. Of the 1,658 171 developed dementia and of those 171, 102 developed Alzheimer’s.

The study found that among people deficient and severely deficient there was a high chance of developing dementia. Deficiency in vitamin D shows with blood vitamin D levels between 25 and 50 nmol/L, and severe deficiency is vitamin D levels below 25 nmol/L.

All in all what this means is that you should go outside and get some sun. Be sure to allow a lot of skin exposure so you can absorb a lot of sun. Just your face and arms might not be enough. Alternatively you can take a vitamin supplement orally to get your vitamin D levels up. Just be sure not to take too much because vitamin D is a fat soluble vitamin and taking too many of those is a big no no.

Link to the study: http://www.neurology.org/content/early/2014/08/06/WNL.0000000000000755.full.pdf