Antioxidants - Can They Halt the Ravages of Time and Disease?
Antioxidants have become a popular buzzword and depending who you
listen to these compounds are credited with everything from curing
cancer to reversing the body clock as well as other more outlandish
claims.
So what are antioxidants? And in what ways (if any) can they help the
human body to heal or strengthen itself?
The theory of how antioxidants work is not hard to understand. However,
as we will see their efficacy, especially in the form of dietary
supplements is still somewhat controversial.
The human body metabolizes oxygen in order to produce energy and free
radicals are a natural by-product of this metabolic process. Free
radicals are atoms or groups of atoms with unpaired or unbalanced
electrons. These volatile particles steal electrons from cells and
other molecules within the body and may cause cell damage in the
process. This cell damage manifests itself as aging and disease.
It is quite normal to have free radicals in the body. However,
excessive quantities have the potential to do significant harm.
Exposure to excessive sunlight, smoking, pollution, alcohol and
radiation are all known to exacerbate the effects of free radicals and
lead to premature aging and/or serious illness.
Free radical damage has far reaching consequences and is implicated in:
Speeding up the aging process
Cardiovascular disease including arteriosclerosis (hardening of the
arteries) - Free radicals react with Low Density Lipoprotein (LDL)
cholesterol causing it to stick to the walls of arteries. LDL or bad
cholesterol is a major contributor to Coronary Heart Disease.
Failing eyesight caused by deterioration in the lenses of the eyes.
Diseases such as Parkinsons and Dementia resulting from breakdown in
cells of the nervous system
Certain cancers which are related to changes in cell DNA
Arthritis caused by joint inflammation
Antioxidants are compounds that mop up free radicals and neutralize
their impact on cells. Antioxidants are present naturally in the food
we eat in varying degrees. Some of the most commonly known antioxidants
are Vitamin C, Vitamin E, the mineral Selenium and Beta-carotene which
is a precursor of Vitamin A. There are however countless other
compounds which function as antioxidants. Some such as lycopene and
anthocyanins are classified as non-nutrient antioxidants which provide
little or no nutritional value but are still valuable for their
antioxidant properties.
Tests with animals have shown a clear link between antioxidant use and
reduction in the incidence of disease. The connection in humans is not
quite as clear cut. There is anecdotal evidence that men who eat large
quantities of tomatoes which are rich in lycopene have a lower rate of
prostate cancer while consumption of tea (high in flavenoids) is
hypothesized to be the reason for lower heart disease among Japanese.
However, results of recent clinical studies have been inconsistent and
inconclusive. One of the first large studies on antioxidants and cancer
found a sharp reduction in gastric and other cancers among Chinese men
and women at risk of gastric cancer when treated with a combination of
Selenium, Vitamin E and beta carotene. On the other hand a 1994 study
on male Finnish smokers found that beta-carotene significantly
increased incidence of lung cancer while vitamin E supplements had no
impact. Similarly a 1999 study on cancer and cardiovascular disease
among women found no benefit from beta carotene supplements. The lack
of conclusive results from the supplementation studies seems to suggest
that antioxidants may be most effective when derived from a healthy and
balanced diet rather than in the form of supplements.
