Antioxidant

Antioxidants are compounds that inhibit oxidation, a chemical reaction that can produce free radicals. Antioxidants are frequently added to industrial products, such as polymers, fuels, and lubricants, to extend their usable lifetimes. Foods are also treated with antioxidants to prevent spoilage, in particular the rancidification of oils and fats.

In cells, antioxidants such as glutathione, mycothiol, or bacillithiol, and enzyme systems like superoxide dismutase, inhibit damage from oxidative stress. Dietary antioxidants include vitaminsA, C, and E. Dietary supplements marketed as antioxidants have not been shown to improve human health.