Glutathione
antioxidant
ApprovedGeneral information about nutrients. No diagnosis, no medical advice. If you take medication, are pregnant or have a medical condition, talk to your doctor before taking supplements.
Overview
Tripeptide and one of the body's own antioxidants.
Interactions
NAC (N-acetylcysteine) is the rate-limiting precursor for glutathione synthesis. Cysteine availability is the bottleneck — NAC bypasses this by providing a stable, bioavailable cysteine source.
Glutathione peroxidase (GPx), the key enzyme that uses glutathione to break down peroxides, contains selenocysteine at its active site. Selenium deficiency renders glutathione less effective.
Research status
Glutathione levels decline by about 10% per decade after age 20.
Top 5 food sources
Expert opinions
Dr. Strunz
Strunz measures intracellular glutathione (GSH). Because oral reduced glutathione is largely degraded by intestinal gamma-glutamyltransferase, he prioritizes precursors: 600 to 1800 mg NAC, 200 µg selenium, 500 to 1000 mg vitamin C, plus glycine and glutamine to supply all three amino acids of the tripeptide. For direct supplementation he recommends only liposomal or S-acetyl-glutathione (500 to 1000 mg), which survive first-pass metabolism. Target: erythrocyte GSH in the upper quartile.
Source: Dr. Strunz
Expert profiles summarise publicly available statements. The named people do not cooperate with Stackwell and have not authorised these summaries. Not medical advice.
Liposomal or acetyl forms preferred for oral absorption. NAC may be more cost-effective.