维生素Ｄ为类固醇衍生物。已知人体内６种Ｄ族化合物中较为重要的２种是维生素Ｄ２（称为麦角钙化醇，来源于植物性食物。）和维生素Ｄ３（称为胆钙化醇，来源于动物性食物，人体内也可合成）。皮下组织的７－脱氢胆固醇经紫外线照射后可转化为维生素Ｄ３，酵母和植物油也... Vitamin D is a steroid derivative. It is known that the two most important of the six D family compounds in the human body are vitamin D2 (called ergocalciferol, which is derived from plant foods) and vitamin D3 (called cholecalciferol, which is derived from animal foods and also from the human body Can be synthesized). Subcutaneous tissue of 7-dehydrocholesterol after UV irradiation can be converted to vitamin D3, yeast and vegetable oil also ...