Is L-Glutathione actually a peptide?

Yes in the strict sense, it is a tripeptide of glutamate, cysteine, and glycine, though it functions primarily as a small-molecule antioxidant rather than a signaling peptide.

Why is oral glutathione absorption debated?

Glutathione can be broken down in the gut, so bioavailability of intact oral GSH is variable; researchers often compare it with liposomal, sublingual, or intravenous forms and with cysteine precursors like NAC.

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Longevity & Anti-aging

Immune

Research Chemical

L-Glutathione

Also known as: L-Glutathione, Glutathione, Reduced Glutathione

L-Glutathione is the body's principal intracellular antioxidant, a tripeptide of glutamate, cysteine, and glycine. It is studied for oxidative-stress defense, detoxification, and skin brightening. Note: Glutathione is a gamma-glutamyl tripeptide antioxidant (a non-standard peptide bond) that acts as a cofactor rather than a signaling peptide.

Mechanism of Action

Glutathione (GSH) is a thiol tripeptide whose reactive cysteine sulfhydryl group neutralizes reactive oxygen species and is the cofactor for glutathione peroxidase in reducing hydrogen peroxide and lipid peroxides. It conjugates xenobiotics via glutathione S-transferases during phase II hepatic detoxification, and recycles oxidized vitamins C and E. In melanogenesis, glutathione inhibits tyrosinase and shifts pigment synthesis from darker eumelanin toward lighter pheomelanin, the basis of its skin-brightening interest.

Half-life: Short in plasma, roughly 10 minutes to a few hours depending on route and form
Administration Routes: oral, intravenous, subcutaneous
Research Status: Research Chemical