Encyclopedia entry · Longevity
Glutathione
Gamma-glutamyl-cysteinyl-glycine
Glutathione is a tripeptide consisting of gamma-glutamyl-cysteinyl-glycine. It is the most abundant intracellular antioxidant in mammalian cells, cycling between reduced (GSH) and oxidised (GSSG) forms. Glutathione synthesis depends on cysteine availability and the rate-limiting enzyme gamma-glutamylcysteine ligase. UK availability includes oral supplements (modest bioavailability), liposomal oral formulations, injectable forms sold by research peptide retailers, and IV glutathione infusions at private UK clinics.
What the molecule is
- · Endogenous tripeptide (gamma-glutamyl-cysteinyl-glycine).
- · Most abundant intracellular antioxidant in mammalian cells.
- · Cycles between reduced (GSH) and oxidised (GSSG) states.
- · Cysteine is the rate-limiting amino acid in synthesis.
What the literature shows
- · Hospital use of N-acetylcysteine (NAC, a cysteine precursor) in paracetamol overdose to restore hepatic glutathione.
- · Animal-model evidence for glutathione decline with age.
- · Clinical-trial work on oral glutathione supplementation (modest absorption).
- · Trial work on liposomal glutathione (improved bioavailability versus standard oral).
UK regulatory status
- · Oral glutathione is sold as a food supplement in the UK.
- · N-acetylcysteine (precursor) is a UK-licensed hospital medicine for paracetamol overdose.
- · Injectable glutathione has no UK marketing authorisation as a medicine.
- · IV glutathione at private UK clinics is offered as a wellness service, not licensed clinical treatment.
Where UK researchers source Glutathione
See PeptideClear Trust Index →Ranked by CoA Trust tier (strong, partial, weak). Editorial commentary on retailers that list Glutathione or compounds in the same category. We take no commission, referral fee or payment from anyone listed here.
Researchers wanting named-stack bundles (Wolverine, KLOW, Glow) and CoAs that can be QR-verified to a named third-party lab.
Research peptide retailer · Wolverine Stack £29.99, BPC-157 single from £14.99
Nottingham-based research peptide retailer (Bio Research Ltd, since 2024). Bundles and stacks are the hero SKU (Wolverine BPC-157 + TB-500, Tesamorelin + Ipamorelin 3:1, KLOW, Glow). Janoshik third-party CoAs published per batch with QR-code verification. 10-vial bulk packs alongside singles. Wholesale tier above 11 vials.
Researchers who want transparent third-party HPLC batch documents and a less hyped brand voice.
Research peptide retailer · Per peptide, varies
UK research peptide retailer with third-party HPLC plus transparent batch documentation. Plays the credibility lane alongside Pure Peptides UK and Tide Labs.
Best for HPLC verification per product
Research peptide retailer · Per peptide, varies
UK research peptide retailer with HPLC-verified purity claims and CoAs included on orders. Operates under research-use-only framing.
Best for per-batch CoA library
Research peptide retailer · BPC-157 5mg £13.99, TB-500 5mg £36
Long-established UK research peptide supplier. 12 years trading, 15,000+ customers. Operates a public CoA subdomain (coa.purepeptidesuk.com) with downloadable per-batch certificates linked from every PDP. Dual-tier purity (Standard vs Premium with endotoxin LAL + heavy-metal testing on Premium).
Best for public per-batch third-party test reports you can view before ordering
Research peptide retailer · Per peptide, varies
UK-based research peptide retailer trading as Midshire Labs Ltd, with a recovery and longevity focused range, 99%+ purity claims and a public bank of per-batch third-party test reports. All products are framed as research use only.
Researchers who weight UKAS lab accreditation specifically and want the loudest external-verification claim in the segment.
Research peptide retailer · Per peptide, varies
UK research peptide retailer leaning on UKAS-verified HPLC as the sole-in-UK trust claim. Narrower catalogue than UKPeptides or Pure Peptides UK but the lab-verification angle is the loudest in the segment.
Where to learn more
- · PubMed search: "glutathione bioavailability" and "GSH ageing".
- · Reviews on the GSH/GSSG redox cycle in cellular physiology.
- · Our function hub: Longevity peptides.
PeptideClear does not sell, dispense, prescribe, or recommend Glutathione for any specific person. This page is editorial commentary on the published preclinical and clinical research literature and the UK retail landscape.
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