The human gut microbiome has been linked to numerous digestive disorders, but its metabolic products have been much less well characterized, in part due to the expense of untargeted metabolomics and in part to the lack of ability to process the data. In this Review, we focus on the rapidly expanding information about the bile acid repertoire produced by the gut microbiome, including the impacts of bile acids on a wide range of host physiological processes and diseases, while also discussing the role of short-chain fatty acids and other important gut microbiome-derived metabolites.