Obese people -- those with a BMI of 30 to 34.9 -- have a 44 percent higher risk of death from any cause compared with those in the most-favorable range, according to a study in the New England Journal of Medicine. iStockphoto.com hide caption

toggle caption iStockphoto.com

A man sunbathes in Malmo, Sweden, in July. Humans (and other animals) make vitamin D when exposed to sunlight. Johan Nilsson/AFP via Getty Images hide caption

toggle caption Johan Nilsson/AFP via Getty Images

A CT scan of the brain shows the cerebellum, a small portion of each temporal lobe, and the sinuses. Andrew Ciscel via Wikimedia Commons hide caption

toggle caption Andrew Ciscel via Wikimedia Commons

Megan Lindsey (right) and her friend Alexandria Bodfish at soccer camp at University of Notre Dame.  Megan, 14, suffered concussions twice this fall while playing soccer. Courtesy of Barbara Wirtz hide caption

toggle caption Courtesy of Barbara Wirtz

Cycling has at least tripled over the past two decades in several big cities across the U.S., including Minneapolis, Chicago and San Francisco. Jonathan Steinberg hide caption

toggle caption Jonathan Steinberg

NPR thanks our sponsors

Become an NPR sponsor