The Peptide Craze Ground Truths Peptides for tanning do exist. Melanotan 1 and Melanotan 2 both work at increasing melanin in the skin. Melanotan 1 takes longer to activate. Melnotan 1 is FDA approved. Melanotan 2 does libido, Tanning from the inside out = Highly Dangerous and Illegal! Many products advertised on social media platforms promising a tan from the inside out or a tan without sun such Your body already makes a hormone that tells your skin to tan. Melanotan 2 is a synthetic peptide engineered to mimic that hormone but in a version that's more potent and longer lasting than