GHK Cu vs AHK Cu: Which Copper Peptide Is More Effective? Best Copper Peptide Serum The top 4 options of 2026 GHK Cu (Copper Peptide) has emerged as one of the most promising regenerative peptides for hair restoration due to its ability to stimulate follicular activity, improve scalp circulation, reduce inflammation, and prolong the PDF) The effect of tripeptide copper complex on human hair growth in vitro AHK Cu Copper Peptide Hair Growth Study (2007) Plain Language Summary Hairgenetix