D2

D2, also known as Vitamin D2 or ergocalciferol, is a form of vitamin D. It is produced by plants and fungi when exposed to ultraviolet (UV) light. It is often added to foods to increase their vitamin D content.

Manufacturers add D2 to foods to fortify them with vitamin D, which is important for bone health. It is commonly found in fortified milk, plant-based milk alternatives, cereals, and some juices. It functions as a nutrient.

Vitamin D2 is permitted for use in the U.S. food supply. The U.S. National Academies have established a Tolerable Upper Intake Level (UL) for vitamin D. Both the Joint FAO/WHO Expert Committee on Food Additives (JECFA) and the European Food Safety Authority (EFSA) have evaluated vitamin D2. Some studies suggest that vitamin D2 may be less effective at raising and maintaining blood vitamin D levels compared to vitamin D3, but it is still considered a source of vitamin D.