About two years ago CBC news had a great segment on vitamin D and cancer rates. Anyone in northern (far south) climate isn't exposed to enough sunlight after

About two years ago CBC news had a great segment on vitamin D and cancer rates. Anyone in northern (far south) climate isn't exposed to enough sunlight after early Fall. Even if you were outside naked all day you'd never get enough sunlight to make enough vitamin D. It's even worse if you have a naturally dark complexion .