Copper-binding signal peptide · Cosmetic ingredient (topical); not an approved drug
A naturally occurring copper-binding peptide used in topical skincare, with small human trials suggesting improvements in skin firmness and fine lines.
✦ 2 min read · 2 sourcesWhat it is
GHK-Cu is a tripeptide (glycine-histidine-lysine) bound to copper, first identified in human plasma in the 1970s and present in many cosmetic products. It is regulated as a cosmetic ingredient, not as an FDA-approved drug, so it is sold for topical skin appearance rather than to treat any disease. Injectable or systemic GHK-Cu is research-grade and not an approved therapy.
How it works
GHK-Cu acts as a signal and copper-carrier peptide, helping deliver copper and influencing extracellular-matrix remodeling. In lab and human skin studies it is associated with stimulation of collagen and elastin production and with antioxidant and anti-inflammatory activity, which is the proposed basis for its skin-firming and wound-supporting effects.
What the evidence shows
Human evidence is limited but real and consists of small topical trials: studies of GHK-Cu creams and eye creams (including one in ~41 women with photodamaged skin) reported improvements in skin firmness, density, thickness, and fine lines versus placebo or comparators. These trials are small, often industry-linked, and short, so the topical cosmetic signal is moderate while claims of systemic or anti-aging benefit from injection are not supported by quality human data.
Quick check
Four questions, ~60 seconds, with a sourced result.
The honest take
A genuinely studied topical cosmetic peptide with several small human skin trials, but not a drug and not validated for injection or systemic use.
Status & safety
Topical GHK-Cu is broadly legal and available in over-the-counter cosmetics. It is not approved as a drug, so any disease-treatment, injectable, or 'systemic regeneration' marketing is unsupported and outside cosmetic regulation. Topical use is generally well tolerated, with occasional irritation; the safety of injected or research-sourced GHK-Cu in humans is not established.
Summaries of published, third-party research for educational purposes. Not medical advice; not a claim of efficacy or safety for any use.
New, plain-language summaries as the literature develops. Educational only — no products, nothing for sale.
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