MyPepShelf.

← Shelf·Endogenous tripeptide antioxidant·XI.

Glutathione.

γ-L-glutamyl-L-cysteinyl-glycine — a tripeptide central to intracellular redox chemistry. Not a novel research compound: characterized biochemically since the late 1800s, structurally by Frederick Gowland Hopkins, 1921.

Every cell in your body makes glutathione and depends on it for redox balance and phase-II conjugation reactions. Concentration is highest in liver tissue. This is the same molecule your cells synthesize, produced synthetically to a research-grade specification.


The 'master antioxidant' framing has a century of biochemistry underneath it and a decade of internet oversimplification on top. The biochemistry is fine; the wellness narrative is mostly running past what the pharmacokinetic literature actually shows.

Straight talk

Straight talk: intracellular glutathione biology is well-characterized. Whether exogenous glutathione — injected, oral, or otherwise — reaches functional intracellular pools at a magnitude that matters is contested. The peptide is real. Bioavailability is the honest question.

What the research studies

The literature, not a summary of it.

Foundational biochemistry (Hopkins, Meister, Anderson) is textbook material. Contemporary pharmacokinetic literature is more debated. Journals: J Biol Chem, Free Radic Biol Med, Antioxidants (Basel). Read the research yourself:

Recommended vendor · Amino Club

≥ 99% by HPLC on the current lot — ILS Laboratories (ISO/IEC 17025).

$38.99 during Fall Sale (was $59.99)

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