Antioxidants and Their Effects on Health
Antioxidants are basically the compounds which are found in various foods and their main function is to neutralize the unstable molecules, popularly known as free radicals released in the body through the process of oxidation. The free radicals have been largely associated with diseases such as cancer, liver complications and heart disease. Foods obtained from plants – fruits, nuts, vegetables and whole grains are the major sources of antioxidants.
Functions of antioxidants
Since they are capable of counterbalancing the effects of the unstable molecules, antioxidants assist in the protection of cell (seen as the origin of cancer, premature aging and other types of related health conditions). Due to a global health concern, athletes have in the recent past shown great interest in foods that contain antioxidants.
This is attributed to the mere fact that these foods are thought to improve performance and faster recovery from workouts. Depending on the nature of the condition – industrial v/s biological systems – the major reason why this is so is that antioxidants basically accept these extra electrons and because there is a variation in the substances and the procedures involved, the potency of the oxidants is varied.
The benefits of antioxidants
During the interaction of certain types of molecules with oxygen, extra electrons appear attached to some molecules in the body. Having been formed, the free radicals which are highly charged may produce successive reaction with a domino effect. The likely danger comes in when the radicals react with vital components of cells like the cell membrane or the DNA. This can make these cells malfunction or even completely die. To avert this problem, the body employs the antioxidants as part of its defense system. Thus, since antioxidants can safely interact with the free radicals and end their chain reaction activities before any of the important molecules are affected, they can be used to remedy or prevent the development of certain diseases.
In the body, there are different types of enzymes which feed on the free radicals; the standard vitamin (micronutrient) antioxidants comprise beta carotene, Vitamin E, and C. In additions selenium, which is a metal in nature, is also critically important for the proper functioning of one of the antioxidant systems in the body and it is sometimes placed in this group. It is clear that these micronutrients are not manufactured in the body and therefore they must be included in the diet.
Foods rich in Vitamin E include nuts, vegetables, whole grains, apricots, fortified cereals, fish oils. The RDA-recommended daily allowance – varies from one gender to other; for men, 15 IU/day; women 12 IU/day
Vitamin C (Ascorbic acid)
This is contained in green peppers, citrus fruits and juices, spinach, kale, broccoli, cabbage, kiwi, cantaloupe and strawberries. The daily recommended allowance is 60 mg and anything above 2000 mg may result to negative side-effect in certain people.
Beta-carotene (a precursor to retinol (vitamin A)
It is found in egg yolk, liver, butter, carrots, milk, broccoli, tomato, peaches, yams, squash, grains and cantaloupe. Since beta-carotene is easily transformed to vitamin A by the body, there is actually no requirement set. However, the RDA is simply expressed as “RE”. But a point to note is that there are no antioxidant properties in vitamin A and if taken in excess amounts, it can cause toxic effects in the body.
Antioxidants and health
According to proven epidemiologic research, there is a risk reduction in the rate of cancer in people who dwell on diets which include vegetables and fruits. The theory here is that the antioxidants contained in these foods protect the victims against cancer. Although, previous studies have not clearly defined the effects of diet supplements containing antioxidants on the risk reduction of cancer development, currently, scientists have intensified their research on the same.
In a study that featured a male smoker cancer victim on an antioxidant diet versus another who did not take the supplement, the results were confusing as there was an increased rate of cancer. It is not yet clear as to why this happened but it raises concern that when antioxidants are not used well, they can lead to adverse health effects.
It is believed that antioxidants play a vital role in slowing down the process of aging and also provide protection against stroke and heart disease; however, this is yet to be proven. Thus according to the public health, it is too early to draw conclusions on the use of antioxidant diet supplement as a way of preventing diseases. Ongoing studies have indicated that in the next few years, more light will be shed on the matter concerning antioxidants and health. Before then, the only advice is for you to ensure that on each day, you eat about five servings of vegetables or fruits and supplement the diet with regular exercise.
It is believed that engaging in endurance exercise enhances the utilization of oxygen in the body by 10-20 times during rest period. As a result, the amount of free radicals produced is increased which in turn raises concern about the dangers tissues and muscles are exposed to by the endurance exercising. However, various concepts have come up and indicate that regularly exercising improves the antioxidant defense system and guards against the free radicals which are induced by exercise. This therefore shows the ability of the body to adapt to various exercise demands. The changes occur slowly by slowly and so it may take some time to realize the results.
1. The Effect of Vitamin E and Beta Carotene on the Incidence of Lung Cancer and Other Cancers in Male Smokers New England Journal of Medicine (NEJM). vol 330 (15) Apr. 14, 1994. pp 1029-1035.
2. A Clinical Trial of Antioxidant Vitamins to Prevent Colorectal Adenoma NEJM, vol 331 (3). July 21, 1994. pp 141-147
3. Prospects for the use of antioxidant therapies.(Review). Drugs 49(3):345-61, 1995 Mar.