Read on to learn about the health benefits, limitations, and possibly negative side effects of taking glutathione supplements.
Glutathione Is an Antioxidant That May Help Fight Oxidative Damage
Without a doubt, the biggest health benefits of glutathione are the result of its antioxidant properties. Oxidative stress, which occurs when the balance of free radicals and antioxidants skews in favor of free radicals, can result in cell damage, according to the National Cancer Institute. (4) Research shows this process is linked to cancer, autoimmune disorders, cataracts, rheumatoid arthritis, cardiovascular and neurodegenerative diseases, and accelerated aging itself. (5) The presence of glutathione helps guard against oxidative stress, and depletion of the amino acid compound is also associated with those disorders, per an article published in February 2014 in Integrative Medicine: A Clinician’s Journal. (6) Research into the benefits of glutathione supplementation often looks at whether replenishing it in the body will help relieve oxidative stress, and therefore improve health and guard against the effects of aging. For instance, glutathione levels are depleted in people with Parkinson’s disease, a neurodegenerative disorder that affects movement. That knowledge has spurred research into whether supplements can help with the symptoms of the illness, such as a small, double-blind, placebo-controlled trial published in the Journal of Parkinson’s Disease in May 2017. (7) Results of the study, in which people with Parkinson’s disease were given intranasal glutathione three times daily over three months, saw their symptoms improve during the trial, but no more than the improvements demonstrated in the placebo group. Eight years earlier, results were published in the journal Movement Disorders of a randomized, placebo-controlled, double-blind, pilot trial of people with Parkinson’s disease who were given glutathione intravenously, which showed “the possibility of a mild symptomatic effect.” (8) Yet the belief that glutathione has a beneficial effect on brain functioning motivates a number of clients that Miller sees at Physio Logic to take oral supplements (which she recommends and takes herself). “Probably 50 percent of our clients take it because they feel some sort of improved brain function from it, or improved cognition,” she says. Nonetheless, most registered dietitians recommend getting nutrients from whole foods rather than supplements whenever possible.
Glutathione Appears to Have a Detoxifying Effect
As mentioned, glutathione is also a detoxifier. “It is responsible for binding to and conjugating a lot of toxins in our liver,” says Danielle Citrolo, PharmD, a manager of scientific and regulatory affairs at Kyowa Hakko USA, which sells an oral glutathione supplement under the brand name Setria. Research indicates that conjugation is a process in the liver in which enzymes such as glutathione help make foreign substances, such as drugs, more soluble and easily excreted by the kidneys. (9) Dr. Citrolo cites the conjugation of Tylenol (acetaminophen), which can cause liver damage in high doses, as an example of glutathione protective benefits. (10) Miller says many of her clients who take glutathione supplements do it believing it can counteract the effects of taking Tylenol or drinking alcohol. “They may take it every time that they have a drink. Or if they go out and drink a little more heavily, they will take glutathione before bedtime to hopefully counteract that a little bit. Also for every time they need to take Tylenol.” Despite the beliefs of those who take them, oral supplements may not necessarily confer all of the health benefits that you receive from the glutathione that is naturally produced by your body. “It has a very low oral bioavailabilty, which means that when you take a capsule of glutathione and it reaches your gastrointestinal tract, a large majority of it gets degraded before it’s absorbed into the bloodstream,” says Seemal R. Desai, MD, a dermatologist at University of Texas Southwestern Medical Center in Dallas. Miller says that to get around that problem, she recommends a liposomal form of oral glutathione, which employs a drug nanodelivery system that encapsulates the amino acid compound in a membrane of lipids (organic compounds that are insoluble in water). Still, research into the effectiveness of liposomal glutathione is early. For example, a one-month pilot study published in January 2018 in the European Journal of Clinical Nutrition found that daily lioposomal glutathione helped increase glutathione supply in 12 subjects, thereby boosting their immune system and lowering oxidative stress. (12) Another type of glutathione supplementation — intravenous — is used around the world for a controversial purpose: to lighten the skin. Some do it to conform to cultural pressures that favor lighter complexions over darker ones, especially in women. It’s true that naturally occurring glutathione can convert melanin to a lighter color and deactivate the enzyme tyrosinase, which helps produce the pigment. Still, the FDA warns, intravenous treatments “are potentially unsafe and ineffective, and might contain unknown harmful ingredients or contaminants. The FDA has not approved any injectable drugs for skin whitening or lightening.” (14) The risk of contaminants or infection from injections is a serious concern, says Oma N. Agbai, MD, a dermatologist at UC Davis Health in Sacramento, California, who specializes in multicultural dermatology. “It’s so unregulated that when someone goes to a med spa or some kind of clinic to get this kind of treatment, you don’t really know what you’re injecting.” If staff are poorly trained in injection techniques, “There is a risk for infection, such as fatal sepsis [blood poisoning],” she adds. In fact, the Food and Drug Administration of the Philippines warned in 2011 that repeated injections of glutathione could lead to kidney failure, blood poisoning, and toxic epidermal necrolysis, a life-threatening infection that causes skin to peel off. (15) Furthermore, there have not been any long-term, large clinical trials to confirm the skin lightening effects of glutathione supplements in any form, though a review article published in 2016 in the Indian Journal of Dermatology, Venereology and Leprology reported that a handful of small, randomized, controlled trials have shown oral and topical supplements to be safe and temporarily effective in lightening skin. (16) Further research is needed before dermatologists like Dr. Desai, who is president of the Skin of Color Society, will recommend them for evening out hyperpigmentation [areas of skin that become darker than the surrounding area]. “We haven’t found a form that really works for skin issues,” he says. In fact, glutathione is not approved at all by the FDA for dermatological use, Desai continues. If someone comes to his office requesting it, he says he would steer them toward other options — “other skin-lightening agents, in-office procedures, some special sunscreens, things like that.” Meanwhile, those who are more concerned with inner health than outer appearance can rest assured that even if they never go near a glutathione supplement, the amino acid compound is nevertheless hard at work performing vital functions throughout their bodies, 24 hours a day, seven days a week.
