A free radical is an atom or molecule with at least one unpaired
electron, making it especially reactive to other atoms or groups of atoms. If
free radicals react with certain chemicals in the body, they may interfere with
the ability of cells to function normally.
At high levels, free radicals may cause cell damage. Some experts
believe that cellular damage caused by free radicals may be a factor in some
age-related health conditions. As a person gets older, the level of damage from
free radicals in the body may increase, leading to cell damage and function
A person may be exposed to free radicals:
Through by-products of normal processes that
take place in the body (such as the burning of sugars for energy and the
release of digestive enzymes to break down food).
When the body
breaks down certain medicines.
Through pollutants, such as heavy
metals and cigarette smoke.
Molecules called antioxidants can interact and stabilize free
radicals. Many dietary antioxidants are vitamins (such as beta-carotene and
vitamins E and C) that occur naturally in fruits and vegetables. Many are also
available as supplements.