Glutathione is produced in the human liver and plays a key role in intermediary metabolism, immune response and health, though many of its mechanisms and much of its behavior await further medical understanding. It is also known as gamma-Glutamylcysteineglycine and GHS. It is a small protein composed of three amino acids, cysteine, glutamic acid and glyceine. Glutatione is found in two forms, a monomerthat is a single molecule of the protein, and a dimmer that is two of the single molecules joined together. The monomer is sometimes called reduced glutathione, while the dimmer is also called oxidized glutathione. The monomer is the active form of glutathione. Oxidized glutathione is broken down to the single molecule by an enzyme called glutathione reductase.
Glutathione, in purified extracted form, is a white powder that is soluble in water and in alcohol. It is found naturally in many fruits, vegetables, and meats. However, absorption rates of glutathione from food sources in the human gastrointestinal tract are low.
Glutathione was first isolated in yeast in 1929. Its metabolism in the body was described in 1984, and its role in cancer treatment dates from 1984.
Glutathione is a major antioxidant highly active in human lungs and many other organ systems and tissues. It has many reported uses. It has a critical role in protecting cells from oxidative stress and maintaining the immune system. Higher blood levels of glutathione have been associated with better health in elderly people, but the exact association between glutathione and the aging process has not been determined.
Among the uses that have been reported for glutathione are:
- treatment of poisoning, particularly heavy metal poisons
- treatment of idiopathic pulmonary firbosis
- increasing the effectiveness and reducing the toxicity of cis-platinum, a chemo drug used to treat breast cancer
- treating Parkinson's disease
- lowering blood pressure in patients with diabetes
- increasing male sperm counts in humans and animals
- treatment of liver cancer
- treatment of sickle cell anemia
Claims made about glutathione have included that it will increase energy, improve concentration, slow aging, and protect the skin.
The importance of glutathione is generally recognized, although its specific functions and appropriate clinical use remain under study. Similarly, because ingested glutathione has little or no effect on intracellular glutathione levels, there are questions regarding the optimal method for raising the intracellular levels.
In addition to ongoing studies of the role of glutathione in cancer and cancer therapy, there are currently clinical trials of glutathione in Amyotrophic lateral sclerosis (ALS). The U. S. National Cancer Institute has included glutathione in a study to determine whether nutritional factors could inhibit development of some types of cancer.
European researchers, with support from the Cystic Fibrosis Foundation, are examining the potential uses of inhaled glutathione in cystic fibrosis. Some physicians also use inhaled glutathione in treating airway restriction and asthma. Other studies are investigating whether administration of alpha-lipoic acid, a material that can elevate intracellular glutathione, may be beneficial in restoring the immune system in AIDS patients.
Although glutathione is marketed as a nutritional supplement, it does not appear that glutathione supplements actually increase the levels of glutathione inside cells. In human studies, oral doses of glutathione had little effect in raising blood levels. Further, glutathione is so widely distributed in common foods that supplements are not normally required. Supplements of vitamin C are more effective at increasing intracellular glutathione than taking oral glutathione supplements. Oral supplements of whey protein and of alpha-lipoic acid appear to help restore intracellular levels of glutathione.
Glutathione is available as capsules of 50, 100, and 250 milligrams. It is also included in many multivitamin and multi-nutrient formulations.
At this time, the only established precautions are sensitivity to any of the inactive ingredients in the preparations of glutathione or the products used to stimulate glutathione levels. This is a discussion of glutathione, not C and whey. There is some new literature that suggests supplementing it may be helpful to some cancer patients, but detrimental to others.
There are no established side effects to glutathione or to the substances used to elevate glutathione levels.
Training & certification
Glutathione has been classified as an orphan drug for treatment of AIDS. For this purpose, medical licensure is required. Glutathione has been given intravenously for amelioration of the side effects of cisplatin therapy. Specific training is required to order, prepare, start, and monitor intravenous therapy. No specific training is required to use glutathione or the compounds which have been reported to raise glutathione levels for other purposes.
Glutathione peroxidase (GSH) is your body’s most abundant natural antioxidant. GSH protects your vision, boosts your immune system, helps turn carbohydrates into energy, and prevents the buildup of oxidized fats that may contribute to atherosclerosis.
Glutathione is a compound classified as a tripeptide made of three amino acids: cysteine, glutamic acid, and glycine. Glutathione is also found in every part of the body, especially the lungs, intestinal tract, and liver. The body produces and stores the largest amounts of GSH in the liver, where it is used to detoxify harmful compounds so that they can be removed from the body through the bile. The liver also supplies GSH directly to red and white blood cells in the bloodstream; it helps keep red blood and white blood cells healthy to maximize the disease-fighting power of the immune system. Glutathione also appears to have an anti-aging affect on the body. GSH levels decline with age, and a lack of glutathione has been shown to leave the body more vulnerable to damage by free radicals, thus speeding up oxidation (wearing down) of the body.
A glutathione deficiency can have a devastating effect on the nervous system, causing such symptoms as lack of balance and coordination, mental disorders, and tremors. Any illness (even a bad cold), chronic disorders such as asthma and rheumatoid arthritis, injury, or heavy exposure to pollutants can cause a GSH deficiency. This is because your body uses more GSH when it is supporting white blood cells and ridding the body of toxins.
Glutathione is found in almost all fruits and vegetables. Acorn squash, asparagus, avocado, cantaloupe, grapefruit, okra, orange, peach, potato, spinach, strawberries, tomato, watermelon, and zucchini are all good sources of GSH. Some vegetables, such as broccoli, cabbage, Brussels sprouts, cauliflower, kale, and parsley, not only provide GSH, but also actually stimulate the body produce more of this powerful antioxidant. Cooking destroys a lot of the glutathione in fresh fruits and vegetables, so you can get the most GSH from these foods by eating them raw or steamed. Eating foods high in glutamine, such as lean meats, eggs, wheat germ, and whole grains, can also stimulate the liver to produce more GSH.
There is no Recommended Dietary Allowance (RDA) for GSH, but supplements have no known harmful side effects. Glutathione supplements can be expensive, but there is some question about the body’s ability to absorb GSH efficiently in supplemental form. If you want to take GSH supplements, just make sure to take them with meals to maximize absorption.
Another, and some say better, way to raise glutathione levels is to take cysteine, glutamic acid, and glycine, the raw materials it uses to make this compound. The N-acetyl form of cysteine (NAC) is easily absorbed by the body, and glutamine supplements are available in a powder that is cost effective, tasteless, odorless, and dissolves easily in water. The usual dose for extra glutamine is anywhere from 1,000 to 5,000 milligrams.
Fish oil, riboflavin (vitamin B2), vitamin C, and selenium also encourage the production and absorption of GSH. In fact, without selenium, a trace mineral that also helps vitamin E work more effectively, the body cannot produce glutathione. Make sure you are getting plenty of these nutrients to help keep your body healthy and strong at any age.
GLUTATHIONE FREQUENTLY ASKED QUESTIONS:
What are the potential advantages of taking glutathione ?
Glutathione peroxidase (GSH) is your body’s most abundant natural antioxidant, and appears to have an anti-aging effect on the body. Advantages of glutathione: Glutathione helps eliminate toxins from the body, and keeps the eyes, central nervous system, and immune system healthy and strong. GSH also helps turn carbohydrates into energy, and prevents the buildup of oxidized fats that may contribute to atherosclerosis.
What conditions or problems is glutathione used for ?
Glutathione peroxidase may help delay the physical effects and problems of aging. Adequate amounts of glutathione are needed to help the immune system fight against free-radical damage, infection, and illness. Glutathione may help prevent or lessen symptoms of conditions like asthma and rheumatoid arthritis.
How much glutathione is enough ?
Unfortunately, there is no Recommended Dietary Allowance (RDA) for glutathione to indicate how much is enough. One hundred milligrams each day is the usual recommended dosage for gluatathione.
How much glutathione is too much ?
Though too much of any supplement may be potentially unhealthy, glutathione supplements have no known harmful side effects.
Are there risks associated with using glutathione ?
There appear to be no risks associated with glutathione supplementation, even in doses of up to several grams a day.
Can you get enough glutathione from food and dietary sources ?
Glutathione peroxidase appears to be found in almost all fruits and vegetables, but it is difficult to get the amount needed for maximum benefit from food and dietary sources alone. Any illness (even a bad cold), chronic disorders such as asthma and rheumatoid arthritis, injury, or heavy exposure to pollutants can cause a glutathione deficiency.
Glutathione peroxidase is available in supplemental form. You can also indirectly raise glutathione levels by taking either the N-acetyl form of cysteine (NAC) or glutamine supplements.
What Is Glutathione?
"Glutathione is a very interesting, very small molecule that's [produced by the body and] found in every cell," says Gustavo Bounous, MD, director of research and development at Immunotec and a retired professor of surgery at McGill University in Montreal, Canada. "It's the [body's] most important antioxidant because it's within the cell."
Antioxidants -- the most well known of which are vitamins C and E -- are important for good health because they neutralize free radicals, which can build up in cells and cause damage. Because glutathione exists within the cells, it is in a prime position to neutralize free radicals. It also has potentially widespread health benefits because it can be found in all types of cells, including the cells of the immune system, whose job is to fight disease.
Glutathione occurs naturally in many foods, and people who eat well probably have enough in their diets, says Dean Jones, PhD, professor of biochemistry and director of nutritional health sciences at Emory University in Atlanta. Those with diets high in fresh fruits and vegetables and freshly prepared meats are most likely just fine. On the other hand, those with poor diets may get too little.
What Does Glutathione Do?
The strong antioxidant effect of glutathione helps keep cells running smoothly. Bounous and another glutathione expert, Jeremy Appleton, ND, say it also helps the liver remove chemicals that are foreign to the body, such as drugs and pollutants.
Appleton is chairman of the department of nutrition at the National College of Naturopathic Medicine in Portland, Ore., and senior science editor for Healthnotes, a database on complementary and alternative medicine available at newspaper stands and health food stores.
Evidence for the important role that glutathione plays in health comes from studies in people who are severely ill.
"If you look in a hospital situation at people who have cancer, AIDS, or other very serious disease, almost invariably they are depleted in glutathione," says Appleton. "The reasons for this are not completely understood, but we do know that glutathione is extremely important for maintaining intracellular health."
How Should Glutathione Be Taken?
Glutathione is probably not well absorbed into the body when taken by mouth. One way to get around that is to take it by vein. A more practical solution is to take the precursors -- that is, the molecules the body needs to make glutathione -- rather than glutathione itself. While there is no solid proof this works, the consensus among experts is that that doing so will increase the amount of glutathione in the cells.
Bounous has developed a glutathione-enhancing product called Immunocal, which is made up of glutathione precursors, mainly the amino acid cysteine.
Who Does Glutathione Help?
Animal and laboratory studies have demonstrated that glutathione has the potential to fight almost any disease, particularly those associated with aging, since free radical damage is the cause of many of the diseases of old age.
"Theoretically, there are many very strong arguments in favor of a therapeutic use of glutathione," says Appleton. "But when people have actually tried to use glutathione as an oral supplement, nasal spray, or intravenously, the results have been more of a preliminary nature. The amount of research on glutathione as a supplement ... is very limited."
Nevertheless, people have tried glutathione for the treatment of a whole host of conditions, including cancer, high blood pressure, Parkinson's disease, Alzheimer's disease, cataracts, and male infertility.
The best studies have been conducted in cancer. One study involved women with ovarian cancer who were being treated with chemotherapy. Some of the women were also treated with intravenous glutathione. Those given the glutathione not only had fewer side effects from the chemotherapy but also had better overall survival rates.
Myriam Abalain of Montreal, Canada, is one of the many people who have taken Bounous's Immunocal to combat cancer. In 1996, at age 33, a routine PAP smear revealed she had precancerous cells on her cervix, which is one step away from having cervical cancer. The three specialists she visited all told her that a hysterectomy was her only option, but she hesitated to have such major, life-altering surgery.
Instead, she waited. For more than two years, her condition remained stable. Then a friend suggested she try Immunocal. After eight months of taking the supplement, her physician could no longer detect any precancerous cells. Does this mean Immunocal cured her? It's hard to say based on just one case like hers. It is possible her body went into remission naturally.
Even Bounous acknowledges there's no real proof his product cured her cancer, but he's working on conducting good clinical research, comparing individuals with cancer taking glutathione to those who are not.
What Are the Risks?
Overall, taking glutathione or its precursors in reasonable amounts appears to be quite safe, although it should be avoided in people with milk protein allergies and in those who have received an organ transplant. There is also some concern, however, about the safety of taking glutathione for the one condition for which there is the greatest evidence of its usefulness: cancer.
"People don't get concerned about these health-promoting [supplements] until they're in their 50s and 60s," says Emory's Dean Jones. At that point, they may already have the initial precancerous [cells]. Therefore, the supplements, just like they promote health in normal tissues, might promote health in the precancerous tissue."
Appleton recognizes this possibility but says "there's no evidence that supplementing with glutathione, even intravenously, is in any way going to make any cancer worse. In fact, the evidence we have suggests the opposite. It suggests that glutathione and other antioxidants, far from interfering with the activity of chemotherapy, appear to reduce side effects without decreasing efficacy and may, in fact, improve the efficacy of the chemotherapy in fighting cancer."
Bounous says his research has demonstrated that taking Immunocal actually lowers glutathione in cancer cells while increasing it in normal cells. As a result, the cancer cells are more vulnerable to chemotherapy, and the normal cells are protected.
The upshot? The experts disagree on who should take glutathione or its precursors. Bounous says everyone should take it in order to optimize overall health. Appleton would reserve it for people with cancer. Jones says it might only prove beneficial for those who eat poorly and are thus unlikely to be getting much glutathione or its precursors in their diet.
They all acknowledge that people with severe diseases known to be associated with low glutathione levels, such as AIDS, may well benefit from the supplement, although there is no proof to this effect.
For her part, Myriam Abalain is still taking Immunocal and feeling fine. "I'm doing pretty good now," she says. "I'm in better shape than ever!"
Source: medicinenet.com -- Glutathione: New Supplement on the Block, by Alison Palkhivala