Melanotan II: Tanning, Sexual Health Benefits, & Safety Concerns 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 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 as injectable Melanotan II Peptide: Tanning, Immunity, and Metabolic Support Revolution Health & Wellness