Lets look at sunless tanning, ., Firstly theres the injections and nasal sprays which typically have an active ingredient called melanotan. This is a synthetic compound that stimulates the Obesity due to MC4R deficiency is associated with reduced cholesterol, triglycerides and cardiovascular disease risk Nature Medicine The Dark Side of Melanotan Tanning Injections: My Personal Experience Revealed Age related ciliopathy: Obesogenic shortening of melanocortin 4 receptor bearing neuronal primary cilia ScienceDirect