Dihydroxyacetone (Dihydroxyacetone)

Dihydroxyacetone is a colorless carbohydrate used as the primary active in self-tanning cosmetics to create a sunless bronzing effect. It reacts with amino acids in the outermost layers of the stratum corneum through a Maillard-type reaction, gradually developing a natural-looking tan tone over several hours without UV exposure. Dihydroxyacetone is widely used in lotions, creams, mousses, sprays, drops, and professional spray-tan systems, often combined with humectants and film formers to improve evenness, longevity, and skin feel. Because the ingredient is sensitive to pH, heat, and oxidation, formulations are typically designed with stabilization strategies (controlled pH, antioxidants, appropriate packaging) and may include complementary colorants for immediate payoff and reduced streaking. For best cosmetic results, products are commonly paired with exfoliation and moisturization routines, and users are advised to apply sun protection since self-tanners do not provide UV defense.