Thus, OXT analogs can be delivered peripherally to improve glucose and insulin profiles, and as suggested by the success of reducing human obesity by peripheral OXT delivery (Figs. 2 and 3), our findings presented in this work propose OXT analogs as a class of peptide targets for the therapy of metabolic diseases including obesity and its related or unrelated diabetes. Here, OXT is linked to obesity due to melanocortin 4 receptor deficiency.