July 30, 2001 -- Who wouldn't like to get their hands on a naturally occurring substance that acts as an antioxidant, an immune system booster, and a detoxifier? Something that can help your body repair damage caused by stress, pollution, radiation, infection, drugs, poor diet, aging, injury, trauma, and burns?
A handful of researchers are saying the antioxidant glutathione can do all that and maybe more. But can you believe such sweeping claims? What's the evidence to back them up? Here are what three experts have to say:
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!"