After a year of using GHK Cu both topically and going deeper than topicals (under my doctor's care), the difference in my skin is not something I have to squint at in good Understanding the Difference Between Glow and GHKCU Peptides GHK CU Infiniwell 7 days on GHK Cu. Here's my honest update. I'm not going to hype this up because the real results don't even start until week 46. But something is already happening.