Palmitic Acid

Palmitic acid is a saturated fatty acid used mainly as an emollient/structurant and as part of emulsifiers (e.g., palmitates, soaps), typically at low-to-moderate concentrations in leave-on products. In its free fatty acid form at cosmetic-use levels it is generally well-tolerated with low rates of irritant reactions in patch testing, though irritation can occur in highly compromised eczema skin or when formulated as alkaline soaps/surfactants. Given its broad use and generally favorable tolerability but non-zero risk in severely reactive patients, a very gentle score is appropriate. Safety Notes: In commercial skincare, palmitic acid is most often used at low levels (~0.05–1%) as a fatty acid/emollient and co-structurant in creams/lotions and as a minor component of emulsifier systems, including leave-on moisturizers and some rinse-off cleansers. Higher levels (~5–15%) are seen where palmitic acid is used deliberately as a primary lipid structurant/opacifier and to boost rich, waxy skin feel in heavy creams and body butters. The upper end (~20–25%) occurs in consumer-available, very high-occlusivity anhydrous balms/sticks and “butter” type products that rely on high fatty-acid/wax solids for structure; there is no specific EU/FDA concentration cap for palmitic acid in cosmetics, so practical sensorial/stability limits typically define the maximum.