Akkermansia muciniphila (Akk) is a mucosal commensal bacterium colonizing the intestinal mucus layer and one of the most abundant microorganisms in the mammalian gut. As a mucin-degrading bacterium, it colonizes the gut of mammals such as humans and mice by utilizing mucin as its sole source of nitrogen and carbon. When colonizing the intestine, its metabolites interact with the intestinal barrier, influencing host health by strengthening the intestinal barrier, regulating metabolic functions of the gut and circulatory system, and modulating immune function. As a promising probiotic, it is also referred to as the "longevity bacterium" and "slimming bacterium" by popular science influencers overseas.