Generation mechanism of gut-derived short chain fatty acids and its dietary regulation.

Short chain fatty acids (SCFAs), as important metabllites of gut microorganisms, organically link the complex interactions between host nutrition and gut microbiota. In recent years, accumulating scientific evidences have well indicated the strong relationship between SCFAs and host health. SCFAs have been found to be both the preferred energy source for intestinal epithelial cells and the natural ligands for free fatty acids receptors. Therefore, SCFAs play a multiple health role. SCFAs are essential in the regulation of lipid metabolism, immunity, inflammatory response, and appetite. The food sources of gut-derived SCFAs precursors, gut microbes involved in SCFAs metabolism and their metabolic pathways were summarized. Dietary approaches on gut-derived SCFAs regulation was further discussed. SCFAs are defined as volatile fatty acids, of which the number of carbon atoms is less than 7. The gut-derived SCFAs, in particular, acetic acid, propionic acid, and butyric acid, are fermented and transformed from SCFAs precursors by...