What vitamin does the sun give you?

Vitamin D synthesis is triggered in the human body when the skin is exposed to ultraviolet rays from the sun, according to the National Institutes of Health Office of Dietary Supplements. Vitamin D is a fat-soluble vitamin that can also be obtained through food and supplements.

Vitamin D has multiple roles in the body, such as supporting bone growth, enabling calcium absorption and protecting the bones from osteoporosis, according to the National Institutes of Health. Because many people wear sunscreen that prevents the absorption of UVB rays necessary for vitamin D synthesis, supplementation is recommended. Cloud cover, smog, season, time of the day and a person's melanin content can all also limit vitamin D synthesis from the sun.