Anti-oxidant —refers to the ability of an ingredient to slow down, prevent, or block oxidation caused by the damaging effects of free radical activity. Some of the most common anti-oxidants used in cosmetics are beta carotene, coenzyme Q10, glutathione, green tea, idebenone, superoxide dismutase, and vitamins C and E. It is well established that a mixture of anti-oxidants may enhance the photo-protective effects of a formulation. Antioxidants are key to age prevention and their daily use in cosmetic products helps reduce UV-induced skin damage.