One of the biggest benefits of fiber is its conversion by microbes in the gut into butyrate, a short-chain fatty acid. Butyrate, in turn, serves as a primary fuel source for the mitochondria in gut cells (colonocytes). It also plays a role in liver cells. One research group found that butyrate directly changes mitochondrial function, efficiency, and dynamics (fusion/fission), and that these changes directly impact insulin resistance, fat accumulation in the liver, and overall metabolism.
