Posts tagged Vitamin D

Vitamin D is unusual among nutrients in that your body can make it from sunlight — specifically, UVB radiation triggers vitamin D synthesis in the skin. For most of human history, this was the primary source. In the modern world, with more time spent indoors, more sunscreen use, more covering clothing, and many people living at latitudes where winter sun is too weak to support synthesis, dietary vitamin D matters far more than it used to. The NIH Office of Dietary Supplements recommends 600 IU (15 mcg) per day for most adults, rising to 800 IU for adults over 70.