GHK-Cu vs Klotho
A neutral, side-by-side comparison of two anti-aging & longevity peptides — their mechanisms, dosing ranges, administration routes, side effects, and research evidence. For research and educational purposes only.
GHK-Cu
GHK-Cu is a naturally occurring copper peptide found in human plasma, saliva, and urine. It plays a role in wound healing, skin regeneration, and anti-inflammatory signaling. Levels decline significantly with age, which has driven interest in topical and injectable supplementation.
Full profileKlotho
Anti-aging protein discovered in 1997 whose deficiency causes a syndrome resembling accelerated aging across multiple organ systems. Circulating soluble klotho declines ~40% from age 40–80. Research into klotho-derived peptides and recombinant protein explores neuroprotection, cardiac protection, renal anti-fibrosis, and metabolic anti-aging benefits. The KL-VS polymorphism provides a natural human model of elevated klotho activity.
Full profile| GHK-Cu | Klotho | |
|---|---|---|
| Category | Anti-Aging & Longevity | Anti-Aging & Longevity |
| Also known as | Copper Peptide GHK-Cu, Glycyl-L-histidyl-L-lysine copper, Copper Tripeptide-1 | α-Klotho, soluble Klotho, KL-VS, klotho protein, KL1 domain |
| Evidence | Research-stage | Research-stage |
| Dosing range | 1mg–3mg mg, daily to every other day (injectable); twice daily (topical) | 1mcg/kg–10mcg/kg mcg/kg, every 3–7 days IV or SC (research) |
| Administration | Subcutaneous injection, Topical application (cream, serum — most common consumer use), Intradermal injection (skincare clinics) | Intravenous (research), Subcutaneous injection |
| Key side effects | Injection site redness (transient), Mild skin irritation with topical (typically resolves with reduced frequency), Rarely reported: metallic taste (with injectable use at higher doses) | Hypophosphatemia (klotho inhibits FGF23 signaling → phosphate wasting), Hypocalcemia (secondary to phosphate effects), Altered vitamin D metabolism, Potential for altered mineral homeostasis with chronic administration |
| Cited sources | 4 references | 2 references |
Key differences
- Administration: GHK-Cu — Subcutaneous injection, Topical application (cream, serum — most common consumer use), Intradermal injection (skincare clinics); Klotho — Intravenous (research), Subcutaneous injection.
- Dosing units differ: GHK-Cu is dosed in mg, Klotho in mcg/kg — they operate at different scales.
- Frequency: GHK-Cu is typically daily to every other day (injectable); twice daily (topical); Klotho is every 3–7 days IV or SC (research).
- Research depth: this profile cites 4 sources for GHK-Cu vs 2 for Klotho.
How each works
GHK-Cu
GHK-Cu has been studied for its ability to stimulate collagen, elastin, and glycosaminoglycan synthesis, promote wound healing, and exhibit antioxidant and anti-inflammatory effects. Gene-expression work by Pickart and colleagues found GHK altered expression (>50% up or down) in roughly 32% of assayed human genes — the basis of the widely-cited '~4,000 genes' figure. Its evidence is strongest for in-vitro and topical/cosmetic use; robust human trials of injectable/systemic GHK-Cu are lacking.
Klotho
α-Klotho functions as both a transmembrane co-receptor for FGF23 (regulating phosphate and vitamin D) and as a shed soluble circulating factor with FGF23-independent longevity effects. Soluble klotho activates longevity-associated pathways: Nrf2/antioxidant defense, FOXO transcription factors, and Wnt/TGF-β inhibition for anti-fibrotic effects. The klotho-deficient mouse ages rapidly and dies young; klotho-overexpressing mice live 20–30% longer.
This comparison aggregates public research and structured profile data for informational purposes only. It is not medical advice and does not recommend either compound for human use. Consult a qualified healthcare provider before considering any peptide.