Active just means the serum contains a functional, lab verified concentration of real GHK Cu copper peptide not just colour or trace copper. Our formula includes 300mg of pure GHK Cu (1% concentration) in Can I Take Glutathione with NAC? Exploring the Synergistic Benefits of Two Powerful Antioxidants Cymbiotika CYMBIOTIKA Glutathione Getting the k'NAC'k of Parkinson's disease The Science of Parkinson's Breaking: more people are starting to explore copper peptides over retinol Not because retinol is bad but because people are beginning to understand how different ingredients actually work. GHK Cu is something your