Peptides are short chains of amino acids that signal specific biological processes. They're not steroids and they're not supplements — they're signaling molecules. Different peptides trigger different biological responses. The ones relevant to this community fall into a few categories:
Collagen-stimulating peptides (GHK-Cu, Matrixyl/Palmitoyl tripeptide-1) — signal fibroblasts to produce more collagen and elastin. Real dermatological research. May thicken and remodel connective tissue.
Tissue repair peptides (BPC-157, TB-500) — promote angiogenesis and tissue healing. Studied for injury recovery. Some interest in tissue remodeling applications.
Growth factor peptides (IGF-1 LR3, MGF) — promote tissue growth through growth factor pathways. Well studied in muscle tissue. Limited data in other tissue types.
Sexual function peptides (PT-141/bremelanotide) — completely different mechanism, targets central nervous system for libido. FDA approved. Not for size.
Very little of this has been formally studied in penile tissue specifically. Most of what circulates is anecdotal. I'll go deeper on each category in follow-up threads.
— PeptidePete