It has been increasingly recognized that parasite derived excretory-secretory products (ESPs), the key substances employed by helminths to downregulate the host’s anti-infection immunity (Harnett, 2014), are able to regulate adipogenesis and improve insulin sensitivity in a high fat diet-induced obesity model (Hussaarts et al., 2015). The gene discussed is INS; the disease is obesity due to melanocortin 4 receptor deficiency.