Vitamin D 1 article

Fat-soluble vitamin D includes two major nutritional forms: vitamin D3, or cholecalciferol, and vitamin D2, or ergocalciferol. Nutrition labels treat vitamin D as a micronutrient, but the form and source can differ across products, so D2 and D3 should not be assumed to be identical ingredients. Food sources include fatty fish and fortified foods, while UV-exposed mushrooms can provide vitamin D2; supplements may use either major form.