What is GHK-Cu?

GHK-Cu is a complex formed when the naturally occurring tripeptide GHK — short for glycyl-L-histidyl-L-lysine — binds to a copper ion. GHK was originally identified in human plasma, and its strong affinity for copper is central to many of the biological effects studied with the copper-bound form.

Researchers are interested in GHK-Cu because it appears to influence processes involved in tissue repair and remodelling. Laboratory studies show effects on fibroblasts, collagen production and other components of the extracellular matrix — the structural framework that helps give skin and connective tissue their strength and organisation.

These findings help explain why GHK-Cu is widely associated with skin quality, wound healing and healthy-ageing research. However, much of this evidence comes from cell and animal studies, so biological activity should not be treated as proof of the same benefit in people.

Human evidence is much smaller. A recent review identified 20 eligible aesthetic studies of GHK-Cu, but 18 were preclinical and only two were randomised controlled trials. In one small study of 13 people after CO2 laser resurfacing, topical GHK-Cu did not significantly improve redness, wrinkles or overall skin quality on objective assessment, although participants reported greater improvement in overall skin quality.