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Longevity & Skin
A natural copper-binding tripeptide with decades of skin research.
Longevity & Skin
The body's main antioxidant — popular for skin lightening, with thin evidence for it.
GHK-Cu is not FDA-approved and rated 3/5 for evidence; Glutathione is not FDA-approved and rated 3/5. They have a similar amount of human evidence. Both are used for longevity & skin goals.
| Compare | GHK-Cu A natural copper-binding tripeptide with decades of skin research. | Glutathione The body's main antioxidant — popular for skin lightening, with thin evidence for it. |
|---|---|---|
| Category | Longevity & Skin | Longevity & Skin |
| Evidence | 3/5Several small human topical/cosmetic studies; injection data is mainly preclinical. | 3/5A handful of small human trials (mostly oral, a few IV) with modest, inconsistent skin-lightening results. Well-studied as a natural molecule, but not as a cosmetic drug. |
| FDA status | Cosmetic ingredient; injectable not approved | Not FDA-approved; oral forms sold as supplements |
| WADA (sport) | Not on the Prohibited List | Not on the Prohibited List |
| Also known as | Copper tripeptide-1, Glycyl-L-histidyl-L-lysine copper | GSH, Reduced glutathione, L-Glutathione, γ-Glutamyl-cysteinyl-glycine |
| How it works | Delivers copper to tissue, stimulates collagen and glycosaminoglycan synthesis, supports wound remodeling, and appears to reset expression of many genes toward a younger profile (gene-expression studies). | Its cysteine thiol (-SH) group neutralizes reactive oxygen species and recycles other antioxidants. For skin, it is thought to shift melanin production from dark eumelanin toward lighter pheomelanin and to inhibit tyrosinase, the enzyme that starts melanin synthesis. How much of an injected dose reaches skin cells is unclear — it is broken down quickly in blood. |
| Half-life | Short (minutes–hours); effects driven by gene/repair signaling | Very short in blood after IV (minutes); levels return to baseline quickly |
| Commonly reported doses |
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| Route | Subcutaneous | Intramuscular or subcutaneous |
| Good once mixed | ~30 days in the fridge | ~14 days in the fridge |
| Top side effects |
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| Lowest research-listing price per mg | $0.35 (100 mg vial, 40% off) | $0.02 (1500 mg vial, 40% off) |
| Latest lab purity | 99.94% (lot GHK0003) | 99.41% (lot GLT0003) |
Want a third? Add another peptide. Doses are commonly reported ranges, not recommendations.
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GHK-Cu is not FDA-approved and rated 3/5 for evidence; Glutathione is not FDA-approved and rated 3/5. They have a similar amount of human evidence. Both are used for longevity & skin goals.
GHK-Cu: Cosmetic ingredient; injectable not approved. Glutathione: Not FDA-approved; oral forms sold as supplements. Regulations change, so confirm with the FDA.
GHK-Cu is rated 3 out of 5: Several small human topical/cosmetic studies; injection data is mainly preclinical. Glutathione is rated 3 out of 5: A handful of small human trials (mostly oral, a few IV) with modest, inconsistent skin-lightening results. Well-studied as a natural molecule, but not as a cosmetic drug. The scale is explained on our methodology page.
GHK-Cu is not named on the WADA list, though the general rule on non-approved substances (S0) can still apply. Glutathione is not named on the WADA list, though the general rule on non-approved substances (S0) can still apply.