Antioxidants are substances that slow or prevent damage to the body’s cells. They protect the cells from unstable molecules known as free radicals, which can increase the effects of aging and the risk of diseases such as cancer and diabetes.

Free radicals are molecules with one or more unpaired electrons. They are a byproduct of a normal bodily process involving the metabolism of oxygen for energy. Environmental factors such as cigarette smoke, air pollution, radiation and ultraviolet light can also cause free radicals to form.

Because free radicals lack an electron, they are unstable and highly reactive. As a result, they steal electrons from other cells, which in turn destabilizes those cells, turning them into free radicals. This chain reaction formation of free radicals can occur indefinitely, causing destruction to the body as cellular damage accumulates.

Antioxidants prevent free radicals from damaging cells by donating electrons to free radicals, thereby stabilizing them. When an antioxidant loses an electron, it remains stable and thus does not itself become a free radical.

There are a number of important substances that supply antioxidants to the body. These include beta-carotene, vitamin C, vitamin E and the mineral selenium.