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Free Radicals and How They are ProducedBecause of attacks from highly reactive compounds called free radicals, every day, every single cell in our bodies experiences about 10,000 oxidative hits to DNA..Many forms of cancer are thought to be the result of reactions between the free-radicals and DNA.Symptoms of aging such as atherosclerosis are also attributed to the radical damage of body chemicals.While the body attempts to protect the cells from this damage some DNA becomes oxidized.Think of this oxidation process as similar to rusting in our bodies. This "rusting" brings on the degenerative ailments of aging, Parkinson’s disease, even potentially Schizophrenia, and Alzheimers disease. Antioxidants neutralize free radicals by donating one of their own electrons. The antioxidant nutrients themselves don’t become radicals by donating an electron because they are stable in either form. Do you know Samuel S. Epstein, M.D. is professor emeritus of Environmental and Occupational Medicine at the University of Illinois School of Public Health, and Chairman of the Cancer Prevention Coalition. He has published some 260 peer reviewed articles, and authored or co-authored 11 books including: the prize-winning 1978 The Politics of Cancer; the 1995 Safe Shopper's Bible; the 1998 Breast Cancer Prevention Program; the 1998 The Politics of Cancer, Revisited. There a a few available below;
How we produce free radicals?
These radicals have an important role to play in our bodies. One of their tasks is to kill bacteria at the intracellular level. Because free radicals are necessary for life, the body has a number of mechanisms and enzymes to minimize free radical induced damage, and to repair the damage that does occur. Bilirubin and uric acid play a part in this, and can act as antioxidants. This is a link to pubmed. An excellent website for researching.
Pubmed where science based research is done. A MUST for any health conscious person.
Normally, the body can handle these radicals, but if antioxidants are unavailable, or if the free-radical production becomes excessive, damage can occur. This is how free radicals are produced. We note that this radical damage accumulates with age. Studies have been done on free radicals and Mangosteen. Antioxidants neutralize these radicals by donating one of their own electrons, ending the electron-"stealing" reaction. The antioxidant nutrients themselves don’t become free radicals by donating an electron because they are stable in either form They act as scavengers, helping to prevent cell and tissue damage that could lead to cellular damage and disease. Antioxidants are believed to help protect the body from free-radical damage. But before you go out and stock your pantry with mega-doses of these vitamins, be warned: more is not always better.The long-term effect of large doses of these nutrients has not been proven. Other chemicals and substances found in natural sources of antioxidants may also be responsible for the beneficial effects.So for now, the best way to ensure adequate intake of the antioxidant nutrients is through a balanced diet consisting of 5-8 servings of fruits and vegetables per day. So we can see that we can armor our cells against free radical damage with nature's powerful antioxidants. If it is difficult to include fresh whole fruit and vegetables in our diet on a daily basis, we can look for assistance in nutritional supplements, keeping in mind that it is important to look for nutritional supplements that bring us the benefit of whole fruit and vegetables. Antioxidants are intimately involved in the prevention of cellular damage -- the common pathway for cancer, aging, and a variety of diseases.The scientific community has begun to unveil some of the mysteries surrounding this topic, and the media has begun wetting our thirst for knowledge. Athletes have a keen interest because of health concerns and the prospect of enhanced performance and/or recovery from exercise.The purpose of this article is to serve as a beginners guide to what antioxidants are and to briefly review their role in exercise and general health. What follows is only the tip of the iceberg in this dynamic and interesting subject. These radicals are atoms or groups of atoms with an odd (unpaired) number of electrons and can be formed when oxygen interacts with certain molecules. Once formed these highly reactive radicals can start a chain reaction, like dominoes.Their chief danger comes from the damage they can do when they react with important cellular components such as DNA, or the cell membrane. Cells may function poorly or die if this occurs. To prevent this radical damage the body has a defense system of antioxidants. Antioxidants are molecules which can safely interact with free radicals and terminate the chain reaction before vital molecules are damaged.Although there are several enzyme systems within the body that scavenge free radicals, the principle micronutrient (vitamin) antioxidants are vitamin E, beta-carotene, and vitamin C. Additionally, selenium, a trace metal that is required for proper function of one of the body's antioxidant enzyme systems, is sometimes included in this category. The body cannot manufacture these micronutrients so they must be supplied in the diet. Vitamin E : d-alpha tocopherol. A fat soluble vitamin present in nuts, seeds, vegetable and fish oils, whole grains (esp. wheat germ), fortified cereals, and apricots. Current recommended daily allowance (RDA) is 15 IU per day for men and 12 IU per day for women. Vitamin C : Ascorbic acid is a water soluble vitamin present in citrus fruits and juices, green peppers, cabbage, spinach, broccoli, kale, cantaloupe, kiwi, and strawberries. The RDA is 60 mg per day. Intake above 2000 mg may be associated with adverse side effects in some individuals.Beta-carotene is a precursor to vitamin A (retinol) and is present in liver, egg yolk, milk, butter, spinach, carrots, squash, broccoli, yams, tomato, cantaloupe, peaches, and grains. Because beta-carotene is converted to vitamin A by the body there is no set requirement. Instead the RDA is expressed as retinol equivalents (RE), to clarify the relationship. (NOTE: Vitamin A has no antioxidant properties and can be quite toxic when taken in excess.) Preventing cancer and heart disease -- do antioxidants help? Epidemiologic observations show lower cancer rates in people whose diets are rich in fruits and vegetables.This has lead to the theory that these diets contain substances, possibly antioxidants, which protect against the development of cancer. There is currently intense scientific investigation into this topic. Antioxidants are also thought to have a role in slowing the aging process and preventing heart disease and strokes. Perhaps the best advice, which comes from several authorities in cancer prevention, is to eat 5 servings of fruit or vegetables per day. Exercise and oxidative damage. Endurance exercise can increase oxygen utilization from 10 to 20 times over resting. Do athletes need to take extra antioxidants? We have read that regular physical exercise enhances the antioxidant defense system and protects against exercise induced free radical damage. This is important because it shows how smart the body is about adapting to the demands of exercise. These changes occur slowly over time and appear to parallel other adaptations to exercise. On the other hand, intense exercise in untrained individuals overwhelms defenses resulting in increased free radical damage.Those who don't do much during the week but have in vigorous exercise during the weekend may be doing more harm than good. Although it is well known that vitamin deficiencies can create difficulties in training and recovery, the role of antioxidant supplementation in a well nourished athlete is controversial. The experimental studies are often conflicting and conclusions are difficult to reach. Nevertheless, most of the data suggest that increased intake of vitamin E is protective against exercise induced oxidative damage. Go to top
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