what the ingredient is
GHK-Cu is a naturally occurring copper-binding tripeptide, present in human plasma and used in cosmetics as a skin-conditioning agent. In formulation it appears on ingredient lists as copper tripeptide-1, and it's responsible for the blue tint you see in many copper peptide products.
the realistic cosmetic benefits
- Smoother-looking skin. Supports the appearance of firmer, more even under-eye texture.
- Better hydration retention. Works alongside humectants rather than competing with them.
- Comfort. Well tolerated at cosmetic concentrations, including on reactive skin.
- Compatibility. Sits comfortably in a simple routine with moisturiser and sunscreen.
what it doesn't do
GHK-Cu is not a pigment lightener, not a filler, and not a medical treatment. It won't remove structural under-eye bags or genetic pigmentation, and any claim that it reverses ageing belongs to marketing rather than to cosmetic science.
how to layer it
Keep copper peptides away from strong direct acids and high-dose vitamin C in the same application — not because of danger, but because you get cleaner results from each when they're separated. Morning patch, evening actives, is the simplest split.
