Niacinamide (Vitamin B3)
Niacinamide (vitamin B3) and niacin are not synthesized in the human body and therefore must be supplied externally, either through the diet or through topical application. Topical application of niacinamide helps eliminate the formation of dark spots and uneven skin tone, as well as reducing redness, irritation and dryness. This active also helps to maintain the synthesis of collagen, involucrin, filaggrin, and keratin. Application of niacinamide is contraindicated for people affected by Parkinson's disease.