Antioxidants are substances or nutrients in our food which can prevent or slow the oxidative damage to our body. Free radicals cause oxidative damage to our body. Free radicals are produced when our cells function normally in the body. Free radicals are damaged molecules which are highly unstable and able to steal components from other cellular molecules, such as fat, protein, or DNA, thereby spreading the damage. This damage continues in a chain reaction with cells becoming damaged and dying.
This process is called oxidation or peroxidation. Peroxidation is useful because it helps the body destroy cells that have outlived their usefulness as well as bacteria and parasites. However, when peroxidation is left unchecked it destroys or damages healthy cells, causing oxidative damage.
Antioxidants act as free radical scavengers and prevent and repair damage done by the free radicals. It does this by binding to the free radicals, transforming them into non-damaging compounds, or repairing cellular damage.
When antioxidants are missing from our diet or are too few, oxidative damage occurs to our healthy cells eg free radicals can damage our immune cells and lead to an increased risk of infections.
Antioxidants come in a variety of forms including vitamin C, vitamin E, the carotenoids and selenium. Good sources are fresh organic fruits and vegetables. The highest concentrations of antioxidants tend to be found in the most deeply or brightly coloured fruits and vegetables.