I am thoroughly convinced that almost everyone is vitamin D deficient. Most of us can get enough through sunlight to prevent signs of deficiency, but if you would be healthier by having more, then why not supplement?

Last year, I heard about high-doses of vitamin D being used to treat a mysterious H1N1 outbreak in the Ukraine. I have since been finding more and more mainstream research supporting the idea that getting the flu, and even the common cold, is strongly correlated with vitamin D deficiency.

“Dr. James E. Dowd, a professor of medicine at Michigan State University and Diane Stafford stated, in their book The Vitamin D Cure, about the flu/vitamin D connection, “More respiratory infections during the winter are probably directly related to lower vitamin D production.” They note several factors contribute to the winter infection scenario. In the winter, there aren’t as much ultraviolet B rays, which inactivate many viruses. With less ultraviolet B getting through, humans produce less vitamin D of their own.” http://thebulletin.us/articles/2009/11/15/top_stories/doc4b004bbeeeca0983629489.txt

Check out this short video by Dr John Cannel of the Vitamin D Council explaining how Vitamin D increases the bodies production of “antimicrobial peptides”
http://www.youtube.com/watch?v=i1iI_d-ZZ0o (a great explanation)

I also found out recently that the way most people shower can prevent sufficient vitamin D absorption even when they are getting a lot of sun
http://www.youtube.com/watch?v=J1sTYuL-QsU (highly recommended explanation from Dr. Mercola)

This is the supplement I’m taking now and recommend: Healthy Origins google product search sorted low to high or Now Foods is also a good brand. I like iherb.com because they are accurate when they say the product is in stock, and they ship out pretty quickly

If you think you are healthy enough, take it because it boosts the brain.

I recommend taking 5000IU or more, and it is very cheap if you buy online.