Isostearic Acid

Isostearic Acid is a branched fatty acid used as an emollient and co-emulsifier that gives lotions and creams a lighter, less waxy feel than straight-chain fatty acids. CIR's review found no irritation or sensitization in human patch testing with the undiluted acid and no photosensitization at 35% concentration under UVA and UVB exposure, and the panel reaffirmed that finding after a later look at newer data.

Cosmetic information for general education, not medical advice. A verdict is a reading of the published evidence, never a guarantee for your skin: any ingredient can irritate someone, so patch test new products and see a professional if you react. Concern is graded on cited evidence, never on hazard-score lists. See how we score.