Let's talk peptides next up: GHK Cu GHK Cu is a copper peptide known for its role in skin health, healing, and overall rejuvenation. Naturally found in the body, it helps support Amazon.com: Skin Perfection Copper Peptide Serum GHK CU 1% for Face & Hair Copper Peptides for Skin, Hair, & Scalp 1% Blue Liquid for Face, Neck, Body, Scalp Multi Use Serum Booster with GHK Cu Hair & Scalp Serum 2400mg 4% Less Shedding Neurogan Neurogan Health Copper Peptides for Skin: The Science, Benefits, and Best Practices Hubmed