Niacin is also known as vitamin B3, or vitamin PP, molecular formula: C6H5NO2, heat resistant, can be sublimated. Nicotinic acid and Nick acid, resistance to infection, skin disease factors. In the human body including its derivatives nicotinamide or nicotinamide. It is one of the 13 essential vitamins, is a kind of water-soluble vitamins, belongs to the vitamin B group. Nicotinic acid in converted into niacinamide, nicotinamide coenzyme Ⅰ and part of coenzyme Ⅱ, participates in the metabolism of lipids and tissue respiration of oxidation process and the process of anaerobic decomposition sugar.