Melanotan II (Tan Jabs): Why They're Not Worth The Risk Dangerous' tanning products promoted by influencers 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 Melanotan What It Is and Its Relation to Skin Cancer Man warns against 'dangerous' tanning injections after turning so dark he 'looked like Madge from Benidorm' and now has the freckled skin of a 60 year old