HERSHEY, Pa. -- Oral supplementation of glutathione is effective in increasing the body’s stores of the antioxidant, said Penn State College of Medicine researchers in study results presented at a conference today (April 22).

Glutathione is involved in protecting cells and tissues from oxidants and other toxins. The effectiveness of orally administered glutathione in enhancing glutathione levels in cells and tissues has been debated.

John P. Richie Jr., professor of public health sciences and pharmacology, presented the study findings -- “Enhanced Glutathione Levels in Blood and Buccal Cells by Oral Glutathione Supplementation” -- at the Experimental Biology 2013 conference in Boston.

The study of 54 healthy adults revealed that glutathione levels of those taking 1,000 mg of an oral supplement of glutathione a day for six months increased 30-35 percent in many compartments including red blood cells, lymphocytes and plasma, and of those taking 250 mg of glutathione increased in whole blood. As glutathione stores increased in the high-dose group, so did the function of natural killer cells, a marker for increased immune defense.

“A battery of immune function markers was examined after three months of glutathione supplementation and natural killer cytotoxicity was enhanced more than twofold for participants taking 1,000 mg daily doses,” Richie said. “We believe glutathione supplementation may represent an effective intervention strategy for disease prevention and may enhance immune function.”

Richie has researched glutathione for more than 30 years, including its role in protecting against oxidative damage during aging and the development of cancer at numerous sites in the body. His research focuses on the factors that regulate glutathione, oxidative stress and cancer risk in individuals and in various populations.