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 PDF) Effects of a Superpotent Melanotropic Peptide in Combination With Solar UV Radiation on Tanning of the Skin in Human Volunteers Watch Me Tan with Melanotan 2 MT2 Year 2 Results, Side Effects, & My Full Protocol MT 1 Age related ciliopathy: Obesogenic shortening of melanocortin 4 receptor bearing neuronal primary cilia ScienceDirect Effects of melanocortin receptor agonists and antagonists on exploratory activity: a review ScienceDirect