Skin, Hair & Cosmetic Peptides: What the Research Shows

The cosmetic peptide category contains the full evidence spectrum in one place: a licensed medicine (afamelanotide) with a narrow, legitimate indication; topical cosmetic peptides with modest but real trial support; oral collagen peptides with a growing consumer-grade evidence base; and an injectable grey-market tanning peptide (melanotan II) that regulators have been warning about for over a decade. Because these compounds share chemistry and naming, marketing constantly blurs them — the licensed drug's existence is used to imply the grey-market analogue is safe.