> and it can provide us with much needed vitamin D Sunlight through your windows won't have any effect on your Vitamin D. The Vitamin D is made by your body i

> and it can provide us with much needed vitamin D Sunlight through your windows won't have any effect on your Vitamin D. The Vitamin D is made by your body in response to UVB radiation, which you get when exposed to the sun. But most windows made in the last 50 years block UVB.