Glutathione
Also: GSH, L-glutathione, gamma-Glu-Cys-Gly
4 papers: 4 human studies.
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Summary
Glutathione is a tripeptide, three amino acids joined together (glutamate, cysteine and glycine), made by nearly every cell in the body and the most abundant antioxidant inside cells. Unlike most substances on this site it occurs naturally in everyone, and the question its research asks is not what it does but whether taking more of it changes anything.
What it targets
Glutathione regulates oxidative stress and supports immune function. A six-month randomised trial in 54 adults found that swallowing it does raise the body's own stores, by roughly a third in red cells, plasma and lymphocytes at the higher intake, settling a question that animal work had left open; that trial measured stores, not health outcomes. Given by infusion, the controlled evidence is thinner: a 21-person placebo-controlled pilot in Parkinson's disease found it well tolerated but produced no significant difference in symptom scores. A separate line of work supplies the building blocks instead of the peptide: a 24-person trial of glycine and N-acetylcysteine in older adults reported improvements in glutathione levels, oxidative stress, mitochondrial function, inflammation and physical function. For skin, a 124-person trial tested oral glutathione with cystine against placebo for lightening, with the combination as the headline comparison rather than glutathione alone.
Clinical Research
Suppliers stocking Glutathione
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