Each human cell is made up of atoms, which contain electrons and protons. In the healthy human cell, atoms contain an equal number of electrons and protons. The electrons occur in pairs, and form an outer layer surrounding the protons.
When the atom loses one of its electrons, this creates an unstable molecule with an unpaired electron. This unstable molecule is called a free radical. The free radical tries to re-stabilize itself by attacking stable, neighboring molecules and “stealing” an electron to replace the one it lost. The molecule that is attacked and loses an electron, in turn, becomes a free radical itself.
The result is a chain reaction that affects an increasing number of neighboring molecules. This chain reaction is called oxidative stress, which is believed to cause chronic diseases such as cancer, arthritis, diabetes and heart disease.
Free radicals form normally in the body through metabolism. However, certain environmental factors can cause an excess of free radicals, such as pollution, cigarette smoke and radiation. Internal factors such as stress can also create excess free radicals.
Oxidation can be prevented by anti-oxidation, which is achieved by molecules called antioxidants. An antioxidant works by donating an electron of its own to a free radical, thereby neutralizing the free radical and stopping the chain reaction of oxidation.
Video: Free Radicals & Antioxidants Explained
This health video explains how free radicals form, how the damage they cause contributes to cancer, heart disease, inﬂammation, neural disorders, diabetes and the symptoms of aging. It also shows how antioxidants neutralize free radical, helping to prevent or reverse the harmful health conditions they cause.