Send me Your FREE
Health & Nutrition Updates

Tips on ways to live longer, healthier and happier.
Enter your email below.

Ask Tufts Experts March 2016 Issue

Q. If you sit in front of a window with sunlight coming through, will your body produce vitamin D or do you have to be outdoors with direct sunlight?

A. The process by which your skin naturally makes vitamin D when exposed to sunlight uses short-wave ultraviolet-B rays (as opposed to long-wave ultraviolet-A rays). According to Bess Dawson-Hughes, MD, director of Tufts' HNRCA Bone Metabolism Laboratory, however, typical car, home and office windows block most UVB rays. So the sunlight coming through a window will not usually make vitamin D.

New to Tufts Health & Nutrition Letter? Register for Free!

Already Registered?
Log In