Natural Vitamin D3

Vitamin D is a fat soluble vitamin and is also considered a hormone precursor that acts on calcium and phosphorus metabolism. It is closely related to sunlight, so it is also known as the "sunshine vitamin". Vitamin D is a general term for a group of compounds with the same structure as A, B, C, and D rings, but different side chains. The structure of A, B, C, and D rings comes from the cyclopentadienyl phenanthrene ring structure of steroids. Currently, there are at least 10 known types of vitamin D, but the most important ones are vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol).

Vitamin D2 is produced by ergosterol in plants exposed to ultraviolet radiation and is less commonly found in nature. Vitamin D3 is converted from 7-dehydrocholesterol contained in the epidermis and dermis of most advanced animals by irradiation with ultraviolet light (wavelength 265-228nm). Vitamin D3 is the most biologically metabolized active form of vitamin D.

Vitamin D3 is fat soluble and insoluble in water. It can only be dissolved in fats or fatty solvents, and can withstand high temperatures and oxidation in neutral and alkaline solutions.