INS and Disorder of lipid metabolism: Prior studies have shown that several Bacteroides species alleviate lipid metabolic disorders; Bacteroides thetaiotaomicron, vulgatus, and acidifaciens were associated with reductions in diet-induced body weight gain, attenuations in atherosclerosis, and improvements in insulin sensitivity, respectively (Liu et al., 2017; Yang et al., 2017; Yoshida et al., 2018).