GHK Cu for hair growth does it actually work? Short answer: no. GHK Cu can be great for skin but when it comes to hair growth, the evidence just isn't there. And this GHK Cu Peptide Progress: Week 3 Results Amazon.com : Bloom Clinically Proven Copper GHK CU Peptide Hair Serum for Hair Growth Non Greasy & Lightweight Advanced Multi Copper Peptides for Thinning Hair Made in USA 3 Pack for 3 Hair Growth Serum Intense with Copper Peptide GHK Cu GHK Cu Copper Peptide for Hair Loss: Results, Mechanism, and What to Expect