Topic summary
Intestinal bacteria
Extracted from the Wikipedia article Gut microbiota.
Overview
The relationship between some gut microbiota and humans is not merely commensal (a non-harmful coexistence), but rather a mutualistic relationship. Some human gut microorganisms benefit the host by fermentingdietary fiber into short-chain fatty acids (SCFAs), such as acetic acid and butyric acid, which are then absorbed by the host. Intestinal bacteria also play a role in synthesizing certain B vitamins and vitamin K as well as metabolizing bile acids, sterols, and xenobiotics. The systemic importance of the SCFAs and other compounds they produce are like hormones and the gut flora itself appears to function like an endocrine organ. Dysregulation of the gut flora has been correlated with a host of inflammatory and autoimmune conditions.