Vitamin D
vitamin D has hormone-like functions as regulators of mineral metabolism
Vitamin D is a group of fat-soluble secosteroids. In humans, vitamin D is unique because it can be ingested as
cholecalciferol (vitamin D3) or ergocalciferol (vitamin D2) and because the body can also synthesize it (from cholesterol) when sun exposure is adequate (hence its nickname, the "sunshine vitamin").