Laboratory work in animals has shown that glutathione levels can be boosted via oral supplementation, but this is the first confirmation in humans, the study’s author’s said. An older, oft-cited study had reported that such supplementation was ineffective.
In the 6-month study sponsored by Kyowa Hakko, which supplies Setria, a branded form of glutathione, 54 participants received either 250 mg or 1,000 mg daily of glutathione. Levels of the endogenous antioxidant increased as much as 250% in the high-dose group, and levels returned to pre-study levels after a one month washout period.
The study, published in the May issue European Journal of Nutrition, also boosted immune system function. The cyctotoxicity of natural killer cells increased two fold in the high-dose group versus placebo.
Boosting marketing potential
The term ‘antioxidant’ may have lost some luster as an overall marketing category as more information becomes available about what these various compounds do and how many ingredients exhibit this activity. But for glutathione, the so-called ‘master antioxidant,’ this plethora of information is turning out to be a good thing, not a confounding factor.
"If you use the term ‘antioxidant,’ well, it almost seems everything is an antioxidant,” Karen Todd, RD, marketing manager for Kyowa Hakko, which supplies Setria, a branded form of glutathione. “We call glutathione the 'master antioxidant' because is it present in all the tissues of your body. It cycles in your organs, especially in your liver and kidneys.”
Glutathione is made in the body, and so cannot be classified as an essential nutrient. But different people’s bodies make different amounts, said Danielle Citrolo, Kyowa Hakko’s technical services manager. And that rate is not always constant.
“Glutathione levels are lowest in the morning,” she said. “And people’s glutathione levels tend to decrease as they age, with people between the ages of 60 and 80 showing the lowest levels.”
“Unless you get up and right away eat some of the foods rich in glutathione, like fresh fruits and vegetables, glutathione supplementation may be called for. That’s why we call it the ‘morning antioxidant,” Todd said. “With this study, we’ve shown that if you do take it orally, it can be extremely effective. It think it will turn heads a little bit.”
“Our next step in research is going to be looking more deeply into the immune health aspects,” Citrolo said.
Source: European Journal of Nutrition
Epub ahead of print, 5 May 2014
“Randomized controlled trial of oral glutathione supplementation on body stores of glutathione."
Authors: Riche JP Jr, et al.