Vitamin D is essential. There are several kinds of vitamin-D, but the two most important forms are D2 (ergocalciferol)and D3 (cholecalciferol). D3 is the form of the vitamin that is synthesized in the skin when we are exposed to sufficient amounts of sunlight or other types of UV-radiation source, but is only producted when the sun is high in the sky. In large areas of Europe, this only happens during the summer period, and there we can only produce sufficient levels of the Vitamin D. Vitamin D3 requires subsequent activation in the liver and kidneys in order to become biologically active.
Vitamin D3 5000IU with Coconut Oil Softgels