The study on high-fat diet seems to provide insights into the relationship between Upd-JAK-IIS under infection condition (156), that is, under infection of parasitic wasps, Upd3 released by blood cells may reduce insulin sensitivity of the muscle and fat body by activating JAK/STAT, thus reducing the anabolism of the muscle and fat body and saving energy for blood cell’s cellular immunity to against parasitic wasp infestation. The gene discussed is SOAT1; the disease is infection.