Vitamin D has two forms: vitamin D2 (ergocalciferol) derived from plant-based sources and vitamin D3 (cholecalciferol) found in some fish and meat and produced by your body when exposed to sunlight.

There are two types of vitamin D supplements available for over-the-counter purchase (vitamin D2 and vitamin D3). Vitamin D3 is the type that most experts believe should be utilized in clinical ...

"It is distinct from other vitamins due to its hormone-like properties, making it unique in both its structure and function .