GHK Cu 50mg Particle Peptides There is no definitive answer as to whether retinol vs peptides are better for anti aging. However, there is a lot more research backing retinol as an effective ingredient, while peptides are still GHK Cu Peptides: Unlocking the Copper Peptide Revolution in Skin Care GHK Cu peptide for collagen support and skin repair GHK Cu vs NAD+: Which Longevity Peptide Should You Take or Stack?