GHK
SkincareAlso known as: Glycyl-L-Histidyl-L-Lysine, GHK Tripeptide, Liver Cell Growth Factor
Emerging ResearchWhat is GHK?
A naturally occurring tripeptide found in human plasma, saliva, and urine. Concentrations decline significantly with age. GHK is the foundation peptide that, when bound to copper, forms the more well-known GHK-Cu. On its own, GHK has wound healing and gene expression modulation properties.
How it works
Activates wound repair and tissue remodeling pathways by modulating the expression of thousands of genes. Increases collagen synthesis, attracts immune cells to wound sites, stimulates glycosaminoglycan production, and promotes angiogenesis. Has high affinity for copper ions, forming GHK-Cu naturally in the body.
What marketers claim
- ▸reverses aging at the genetic level
- ▸resets gene expression to youthful patterns
- ▸superior to GHK-Cu
- ▸regenerates all tissue types
What evidence supports
- ✓gene expression studies show GHK can upregulate genes associated with tissue repair and downregulate inflammatory genes
- ✓stimulates collagen I and III synthesis in fibroblast cultures
- ✓promotes wound healing in animal models
- ✓plasma levels decline from ~200ng/mL at age 20 to ~80ng/mL by age 60
Research evidence
Key studies on GHK, summarized in plain language. This is not an exhaustive list — it highlights the most relevant findings.
GHK peptide as a natural modulator of multiple cellular pathways in skin regeneration
Finding: Comprehensive review concluding that GHK influences wound healing, immune regulation, and tissue remodeling through gene expression modulation. Identified GHK as a potential anti-aging and wound-healing agent.
Limitation: Review paper synthesizing mostly in vitro and computational data. Direct clinical evidence for free GHK (non-copper) skin applications is sparse.
Best for
Safety notes & concerns
Full safety guide →- ⚠most research is on GHK-Cu (copper-bound form) rather than free GHK alone
- ⚠gene expression modulation studies are primarily computational (Broad Institute Connectivity Map data)
- ⚠clinical evidence for topical free GHK (without copper) is limited compared to GHK-Cu
- ⚠difficult to distinguish effects of free GHK from GHK-Cu in biological systems since they interconvert
Pairs well with
Use caution with
Frequently asked questions
What is the difference between GHK and GHK-Cu?
GHK is the base tripeptide; GHK-Cu is GHK bound to a copper ion. In the body, GHK readily binds available copper, so the distinction may be less important biologically than it appears. In skincare, GHK-Cu is far more commonly used and researched. Free GHK formulations are less common and less studied for topical applications.
Does GHK really affect thousands of genes?
Computational analysis using the Broad Institute Connectivity Map found that GHK can modulate the expression of approximately 4,000 genes. However, this data comes from cell-based gene expression profiling, not clinical studies. Whether topical application produces the same gene expression changes in living skin is unproven.
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fine lines, aging skin, anti-aging prevention
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expression lines, forehead wrinkles, those seeking a step up from Argireline
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Last updated: 2025-03-25
Medical Disclaimer
The information on this site is for educational and informational purposes only. It is not intended as medical advice and should not be used to diagnose, treat, or prevent any condition. Always consult with a qualified healthcare professional before starting any new supplement, peptide, or treatment protocol.