GHK Cu is the compound your body made at 25 and quietly stopped making. Most people find it in overpriced serums. Few understand what it actually does, or what happens when you're not Frontiers Exploring the beneficial effects of GHK Cu on an experimental model of colitis and the underlying mechanisms Why does Glycyl Histidyl Lysine Copper (GHK Cu) cause pain or discomfort? GHK CU GHK Cu Peptide Before and After Results