Antioxidants are ingredients that support the skin against the visible effects of environmental factors. Daily life exposes skin to pollution, UV and other factors that can increase unstable molecules called free radicals.
Antioxidants help balance these free radicals, supporting the skin's appearance. Common examples include vitamin C, vitamin E and niacinamide, added to help skin look vibrant and healthy.
Antioxidant products should be seen as part of a holistic routine alongside sun protection and barrier care. What matters is the whole formulation, not a single ingredient. Consult a physician for choices suited to your skin.