IL22 and Cachexia: Although Wang et al. reported that IL-22Fc treatment reduced fat pad size in HFD-fed mice, they did not analyze body composition, nor did they examine the effect of IL-22Fc treatment on body weight in lean mice, so we can’t rule out the possibility that the weight-reducing effect of IL-22Fc treatment in HFD-fed mice was due to cachexia caused by super high levels of IL-22.