Used primarily as a fat-soluble antioxidant in cosmetic and pharmaceutical formulations. It helps stabilize oils and prevent rancidity by scavenging free radicals, extending shelf life of lipid-based products. Commonly added to skincare products for its potential to support collagen synthesis and reduce oxidative stress in the skin, offering anti-aging benefits. Its lipophilic nature allows better incorporation into creams and ointments compared to water-soluble vitamin C, enhancing skin penetration. Also used in some food products to protect against oxidation while providing a source of vitamin C activity.