INS and type 2 diabetes mellitus: In a cohort study in the Chinese population, it was reported that a decrease in the abundance of A. muciniphila was associated with impaired IR in subjects with T2D because A. muciniphila modulates insulin secretion through the levels of 3 β—serum chenodeoxycholic acid, inducing glycogen synthesis and suppressing gluconeogenesis, thereby improving glucose tolerance [32].