You may have heard about the health benefits of antioxidants, but do you know what an antioxidant is -- and how they actually work?

Antioxidants are dietary substances including some nutrients such as beta carotene, vitamins C and E and selenium, that can prevent damage to your body cells or repair damage that has been done.

Antioxidants work by significantly slowing or preventing the oxidative -- or damage from oxygen -- process caused by substances called free radicals that can lead to cell dysfunction and the onset of problems like heart disease and diabetes. Antioxidants may also improve immune function and perhaps lower your risk for infection and cancer.

In your body, the antioxidant process is similar to stopping an apple from browning. Once you cut an apple, it begins to brown, but if you dip it in orange juice, which contains vitamin C, it stays white.

An eating plan containing plenty of fruits and vegetables, whole grains and nuts can supply all the antioxidants your body needs.