Free Radicals

The human body is made up of cells. Cells are made up of molecules, and molecules are made up of atoms. Atoms contain the following components:
- a nucleus-the center of the atom
- protons-positively-charged particles in the nucleus
- neutrons-particles in the nucleus that have no charge
- electrons-negatively-charged particles circling the nucleus in layers called shells

Electrons always travel in pairs-or at least they prefer to travel that way. Occasionally, though, an atom or a group of atoms (a molecule) may lose one electron. When this happens, the atom or molecule becomes a free radical.

Like the human body in general, atoms prefer stability. An atom that's missing an electron will steal one from the nearest stable atom-turning that atom into a free radical. As you can probably imagine, this is the start of a chain reaction.

What causes free radicals?
Free radicals are created as a result of the process of oxidation, when a substance combines with oxygen. This is part of the body's normal metabolism, and does increase with age. Free radicals can also be created by the immune system to help destroy bacteria and viruses during an infection. And they can form as a result of exposure to certain chemicals, environmental toxins like pollution and radiation, and cigarette smoke.

Under normal circumstances the body can easily rid itself of free radicals. But problems can occur if the number of free radicals increases beyond the body's ability to neutralize or destroy them.