Any ingredient that reduces certain signs of inflammation, such as swelling, tenderness, pain, itching, or redness. Many ingredients perform the function of anti-irritants or anti-inflammatories, and better ones are being discovered all the time. Interestingly enough, most antioxidants function as anti-irritants because one of the skin’s responses to free-radical damage is irritation and inflammation. These ingredients go a long way toward helping the skin deal with its daily struggle against sun exposure, pollution, skin-care routines (topical disinfectants, sunscreens, and exfoliants can be irritating to skin), and seasonal environmental extremes (Sources: Exogenous Dermatology, June 2004, pages 154–160; and Toxicology Letters, December 2003, pages 65–73).