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Minggu, 21 Juni 2009

Antioxidants and Free Radicals

Antioxidant nutrients can reduce your risk of developing dozens of degenerative diseases, including heart disease, arthritis, and cancer. Antioxidants also slow the aging process, prevent cataracts, and contribute to a longer and higher quality of life. Study demonstrates that oxidized LDL is the real culprit in heart disease.
Oxidation at the cellular level in humans is not unlike the rusting of iron. An electro-chemical reaction produces physical damage that can result in cell impairment, cell genetic damage leading to unpredictable replication(cancer), or cell death.
What is an antioxidant?
Anything that slows the oxidative process can be called an antioxidant. Included in this catagory are vitamins E and C, enzymes, coenzymes, and sulfur-containing compounds, such as glutathione. Dietary antioxidants include vitamins E and C, along with carotenoids(lipid-soluble plant pigments) and flavonoids(water-soluble plant pigments), and several sulfur-containing compounds, including MSM(methylsulfonylmethane), lipoic acid, and L-cysteine and methionine, both amino acids. Antioxidants have the ability to quench free radicals by donating electrons. The best antioxidants donate the most electrons, but that is an oversimplification. Antioxidants work together as a network, some extending the life of others, particularly vitamins C and E which are replenished by such substances as pycnogenol, grapeseed extract, carotenoids, and other flavonoids.
What is a free radical?
An atom consists of a nucleus with protons and neutrons, and pairs of electrons orbiting this electrically-charged space. The behaviour of the atom depends on the number of electrically-charged particles. When, during a chemical reaction, an electron is pulled from one of the pairs of electrons of an oxygen molecule, that oxygen molecule with an unpaired electron becomes a free radical. This is so because it must seek out another electron to make a new pair, and may cause damage by pulling an electron from an otherwise normal cell of your body. That's not all. The newly damaged molecule is now itself left with an unpaired electron and must scavange an electron in what has now become a "cascade" of free-radical damage. Depending on the amount of antioxidants available and the level of exposure to chemicals, insufficient diet, immune suppression, etc., there can be thousands and thousands of free-radical events taking place in one's body at any given moment. So the existance of sufficient antioxidants, both made by the body, and derived from the diet, can mean the difference, quite explicitly, between health and disease.
What is the Antioxidant Network?
Richard Passwater,PhD., an authority on antioxidants, has put it this way: "Antioxidants should not be thought of as individual compounds. They should be thought of as complementary players on a team, or in the way that individual instruments form an orchestra." Dr. Denham Harman of the U. of Nebraska demonstrated back in 1968 that large amounts of vitamin E increased life-spans of mice by 5%. Soon after, Dr. Passwater demonstrated that a synergistic combination of then-available antioxidants increased life-spans by 30%, with considerably lower amounts of vitamin E needed. Now it has been established that different antioxidants work in different ways, in different parts of the cells and body fluids, yet, at the same time, they can regenerate or recycle other weakened antioxidants by donating electrons to them. In this way, alpha-lipoic acid and pycnogenol, for example, extend the usefulness of vitamins C and E, while still performing their unique parts in the antioxidant "orchestra".
What Kind of Damage?
It is estimated that every cell in your body suffers in the neighborhood of 10,000 free-radical "hits" per day, much of this damage being done to the genetic material in the cell. This worsens with age. Elderly persons have nine times the frequency of cell mutations as infants. In addition, cell membranes, proteins, and fats are also damaged by free-radicals. The fatty tissues are especially susceptible to oxidation. This is called "lipid peroxidation". This can be seen in skin that looks dry. Damaged protein(and enzymes, which are made of protein) can result in premature wrinkling, aging, or even cancerous growths on the damaged skin. The same process can be going on anywhere inside the body as well, wherever there are insufficient antioxidants to "quench" the electron-stealing free radicals.
Intriguing research on Chromosomal abnormalities and cancer. The doctor reminds us that half or more of all carcinogens are not mutagenic.

Direct Link Found between Inflammation and Cancer. And inflammation results from the oxidative reactions described above and below.

Can I reduce my exposure to free-radicals?
Yes. Avoid tobacco smoke and smog. Stay away from high-fat, high-sugar, over-processed foods. Reduce exposure to solvents, chemicals, and synthetics. Get some excercise, but don't overdo it. Drink distilled water. Supplement with antioxidants like Co-EnzymeQ10, Alpha-Lipoic Acid, MSM, DMG and Resveratrol, Grape-Seed extract, and, of course vitamins C and E. Try to reduce stress, which increases free-radical production. Stress causes increased production of adrenaline, which activates blood platelets so they have a greater tendancy to clump together and form a blood clot. Studies conducted in Germany by Peter Rohdewald, PhD., and confirmed by Dr. Ronald Watson of the U. of Arizona, Tucson, found that pycnogenol(pine bark) blocks the effect of adrenaline on blood platelets, without causing increased bleeding(as with aspirin).

Antioxidants protect against cancer in at least three ways: by destroying cancer-causing free radicals, by boosting the body's immune system so it can destroy mutated cells, and by reducing the tendency of cancer cells to adhere to other organs and glands. Molecules called "cellular adhesion molecules" are implicated in cancer establishment as well as in inflammation, allergies, and atherosclerosis. By reducing their activity, antioxidants may protect against diseases and disorders in yet undiscovered ways. It may be that all degenerative disease is linked in some way to the activity of free radicals. According to Lester Packer, PhD., of the U. of California at Berkeley, a leading researcher in the field of antioxidants, "the prospects for life extension and life enhancement with antioxidants have never looked better."

Of course, free radicals are not the only issue here. We need enough B-vitamins to prevent build-up of homocysteine, which acts somewhat like a free radical in that it damages the cells that line the arteries. And homocysteine levels are regarded as part of the 'Inflammation Syndrome', 'Metabolic Syndrome,' or 'Syndrome X' as it has variously been described. This is a complex of symptoms, including high cholesterol, high blood pressure, high blood sugar, and high levels of insulin in the blood. Medical doctors tend to treat each element of the syndrome with a specific drug therapy, but even the AMA has admitted this is probably not the best way to deal with the issue. The January, 2002, issue of the JAMA, stated: "... it seems unlikely that management of the individual abnormalities of this syndrome provides better outcomes than a more integrated strategy." (JAMA, 3, 297, p.359, 2002). And that integrated strategy includes not just antioxidant supplements, but life-style changes including excercise, reduced trans-fatty acids, salt, and sugar(margerine, prepared foods for example), B-vitamins, and stress-reduction. Don't be a couch potato!

Berries could contain the best antioxidants in cancer prevention.

What's the future of Antioxidant research?

Thousands of articles on antioxidants appear now each year in medical and scientific journals. The bottom line is that free radicals damage genes and activate "bad" genes, whereas antioxidants protect genes and activate healthy responses from within the very cells themselves, as well as from the immune system as a whole. These are some of the most important discoveries of the 20th and 21st centuries. Scientists will increasingly focus on the molecular and atomic level of these reactions to determine the unique roles played by the different players on the "team."

Says Donald J. Reed, PhD, Distinguished Professor of Biochemistry, Director, Environmental Health Sciences Center, of the Linus Pauling Institute, “ATP carries chemical energy in cells. In diseased mitochondria ATP energy is not put to useful work but is released instead as heat. Examples of adverse heat production in biological systems are inflammation associated with arthritis and fever stimulated by infection. Antioxidants such as vitamin C, vitamin E, lipoic acid, carnitine and coenzyme Q10 work inside the mitochondria to help maintain its proper function.”

Dietary supplementation with antioxidants may protect the mitochondria against respiration-linked oxygen stress, with preservation of the genetic and structural integrity of these energy-producing cell bodies.

To quote another recent report: “Mitochondrial damage caused by reactive oxygen species and concomitant decline in ATP synthesis seem to play a key role not only in aging, but also in the fundamental cellular process of apoptosis (cell death). Although dietary supplementation with antioxidants has not been able to increase consistently the species-characteristic maximum life span, it results in significant extension of the mean life span of laboratory animals. Presently, the focus of age-related antioxidant research is on compounds, such as coenzyme Q10, alpha-lipoic acid, and the glutathione-precursors like N-acetylcysteine, which may be able to neutralize undesirable reactive oxygen species at their sites of production in the mitochondria.” [Ann NY Acad Sci 959:508-16, 2002]

Science Daily, 1/25/02: Antioxidant prevents Type 1 diabetes in lab animals.

A Baylor College study finds liver damage results from lack of an antioxidant(N-Acetyl Cysteine). They want to patent a new drug to treat the issue. We say, choose your antioxidants wisely.

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