Is it necessary to cycle on and off of every peptide? The answer may not be as simple as you think, and it depends on *why* the peptide is being used. The GHK Cu (Copper Peptide) is a naturally occurring peptide in the body that binds with copper to support cell repair and renewal. As we age, our levels decrease and thats where supplementation or GHK Cu Peptide: Benefits for Tissue Repair, Healing, and Recovery Revolution Health & Wellness GHK Cu Peptides for Research 99% Purity Guaranteed