But if you’ve been shopping the supplement aisle, you must have noticed that there isn’t just one form of vitamin D: vitamin D2 and D3 are called out on various labels, too. What exactly is the ...

vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol). While both forms serve similar functions in the body, there are differences in their sources, metabolism, and effectiveness.

Here's what you need to know about the differences between vitamin D2 and D3. Vitamin D is not actually a vitamin, but a hormone that affects many of your body's important functions. It "is ...