Irisin activates the browning of white fat and the expenditure of energy together with increased expression uncoupling protein 1 by stimulating the p38 and extracellular‐regulated protein kinase (ERK) signalling pathways, and thus, irisin ameliorates diet‐induced obesity and insulin resistance in vivo15. This evidence concerns the gene FNDC5 and obesity due to melanocortin 4 receptor deficiency.