As I mentioned above- Vitamin-D is not absorbed well orally. Researchers have run tests measuring the amount of Vit-D in the blood and find that most of what is taken orally is just excreted. It is much more efficient to get it from sunlight because then it goes right into the bloodstream from the skin capillaries. It's the way nature intended this vitamin to be gotten. And it doesn't require roasting your skin- only exposing enough that no one area has to do all the work.