What is GHK-Cu and what are its benefits?

GHK-Cu (Copper Glycyl-L-Histidyl-L-Lysine) is a naturally occurring copper peptide found in human plasma, saliva, and urine. Research shows it declines with age from about 200 ng/mL at age 20 to 80 ng/mL at age 60. GHK-Cu modulates gene expression, influencing approximately 4,000 genes related to tissue repair, collagen production, antioxidant defenses, and anti-inflammatory responses. Benefits may include: improved skin appearance (reduced wrinkles, increased firmness), accelerated wound healing, hair growth stimulation, anti-inflammatory effects, and tissue regeneration. It can be applied topically in skincare products or administered via subcutaneous injection. Topical formulations (serums, creams) are widely available in skincare markets, while injectable forms are less common. Research suggests GHK-Cu is generally well-tolerated with low toxicity. However, most human data comes from small studies or cosmetic applications rather than large clinical trials. It's not FDA-approved as a drug but is used in cosmetics and research contexts.