Antioxidant means: Anti– (from Latin) is “against,” “opposed to” and oxidant refers to reactive molecules produced during the body’s oxygen metabolism or created from environmental causes. Antioxidants, therefore, are those molecules responsible for reducing those reactive molecules which are free radicals and oxidants. Free radicals and oxidants have been implicated as one of the causes of disease.
The body uses oxygen for many of its biological functions, like enzyme reactions, immune response, producing energy, and the biochemical reactions that create vision. Free radicals and oxidants are created as a by-product of these reactions. Free radicals and oxidants in the body are created two ways:
- as a normal by-product of cell metabolism, or
- from external assaults to the body, like radiation and UV light, cigarette smoke, pollution, or medications.
The body can create its own antioxidants, but when there is an imbalance, meaning there are more free radicals then there are antioxidants, a phenomenon called oxidative stress occurs. Oxidative stress means there is a surplus of these reactive particles running around which have the capability to attack healthy cells. Healthy cells under oxidative stress become dysfunctional resulting in degeneration. Degeneration results in aging and disease.
The body combats oxidative stress by producing its own antioxidants and utilizing foods as a source of naturally occurring antioxidants. The role of the antioxidant is to “scavenge” for free radicals to prevent cellular damage. When an imbalance exists, and the body is under oxidative stress, and a nutritional diet does not supply enough antioxidants, supplementation is necessary.
Clinical Studies and Antioxidants
While most studies of eye disease agree that oxidative stress in the eye is a cause of the degenerative diseases of macular degeneration and cataracts, the role of antioxidants is less certain. The macula, which is responsible for seeing the fine line and detail of the central vision, consumes a lot of oxygen and is assaulted by UV light radiation. For these reasons this very sensitive area is predisposed to oxidative stress. The pigments lutein and zeaxanthin are thought to have a protective role by absorbing UV radiation. Vitamin C and Vitamin E are two antioxidant vitamins studied because it is thought that they may prevent and protect the macula from oxidative damage.
The lens of the eye not only serves to focus the light to the macula, but also serves to absorb UV light. It is the light radiation that creates oxidative stress within the lens that results in cataracts. While it is not certain what the role antioxidants supplements play in reducing the risk for cataracts, it is known that the levels of vitamin C decrease with age, suggesting that cataracts increase as antioxidants in the lens decrease.
Dietary Sources of Antioxidants
Nothing new here: a nutritious diet rich in fruits and vegetables.
- Vitamin C
- Vitamin E
- Omega 3 and Omega 3 Fatty acids
As with any other supplements, check with your doctor before launching into a supplement regiment high in antioxidants. While antioxidants are necessary for protection and prevention of disease, excessive dosing of some can be harmful.