Oral supplementation with glutathione can increase the body’s stores of the antioxidant, and could influence immune function, according to new findings from Penn State College of Medicine.
Six months of supplementation with Kyowa Hakko’s Setria Glutathione at a daily dose of 1,000 milligrams were associated with 30-35% increases in glutathione levels in many compartments including red blood cells, lymphocytes and plasma.
The study’s findings appear to end debate over whether oral glutathione administration can effectively enhance the body’s glutathione levels, a debate which has simmered for years.
Presenting the findings at the recent Experimental Biology conference in Boston, John Richie, Jr, PhD, professor of Public Health Sciences and Pharmacology at Penn State College of Medicine, explained that there is a school of thought that contends that glutathione is broken down in the stomach and intestine and effective increases of glutathione (GSH) must come via intravenous administration.
However, previous animal studies showed that orally administered glutathione is bioavailable and will enhance tissue GSH levels, he added.
“Our research showed that in most cases increases were dose and time dependent, and levels returned to baseline after a one-month washout,” he said. “By taking daily GSH supplements, we believe efficacious levels will persist, and that oral intake is an effective means of chronically enhancing the body’s stores.”
Dr Ritchie also presented data that showed that, as glutathione stores increased in the high-dose group, so did the function of natural killer (NK) cells, a marker for increased immune defense.
“A battery of immune function markers was examined after three months of glutathione supplementation and NK cytotoxicity was enhanced more than two-fold for participants taking 1000mg daily doses,” he said.
“We believe GSH supplementation may represent an effective intervention strategy for disease prevention and may enhance immune function.”
The Penn State study involved 54 healthy adults randomly assigned to one of three groups: The first group received placebo, while the second and third groups received 250 and 1,000 mg of Setria Glutathione, respectively.
After six months of supplementation, the results indicated that the 1,000 mg dose increased GSH levels in many physiological compartments, while the 250 mg dose increased GSH in whole blood.
An enhancement in NK cell cytotoxicity was also observed for the high dose group.
In addition, no side effects were observed in the glutathione groups, said the researchers.
“GSH supplementation may represent an effective intervention for disease strategy,” they concluded.
Speaking with NutraIngredients-USA at this week’s SupplySide MarketPlace show in New York City, Danielle Citrolo, Pharm.D., technical services manager for Kyowa Hakko USA, said: “This study shows that the benefits are two-fold. It shows that oral glutathione supplementation enhances glutathione levels in cells and tissues, and there is an effect on immune function.”
Dr Citrolo added that the results will be published in a peer-review journal by the end of the year.
Consumer awareness of the ingredient is improving, but it is still relatively low, at about 5%, added Karen Todd, director of marketing at Kyowa Hakko USA. (Compared to 95% for vitamin C, and 80-85% for fish oil). “Glutathione doesn’t role off the tongue,” she noted, “but lutein was like that several years ago.”
The study was funded by Kyowa Hakko.
Source: Experimental Biology 2013
Boston, April 22, 2013
“Enhanced Glutathione Levels in Blood and Buccal Cells by Oral Glutathione Supplementation”
Authors: J.P. Ritchie, Jr., S. Nichenametia, A. Calcagnotto, W. Neidig, T. Schell, J.E. Muscat