Vitamin D levels in USA peak in August, study finds

A bright spot for our health this summer is that we can get a dose of the sunshine vitamin. Even though our bodies can produce the most vitamin D in June, when the sun is highest in the Northern Hemisphere, vitamin D levels in the USA peak in August, according to a new study. The sun is lowest in December, but Americans' vitamin D levels bottom out in February. Researchers from the University of California-Irvine and the Mayo Clinic in Rochester, Minn., measured the level of 25-hydroxyvitamin D in 3.4 million blood samples collected weekly from July 2006 to December 2011 in the USA. The study was published in the journal PLOS ONE. http://www.usatoday.com/story/news/nation/2013/06/29/vitamin-d-levels-seasonality/2453955/