The preferred fuel of colon cells
Butyrate is a short-chain fatty acid produced when gut bacteria ferment dietary fiber. Unlike most cells, colonocytes lining the large intestine derive the majority of their energy from butyrate rather than from blood glucose, oxidizing it directly in their mitochondria. This local fuel supply supports the integrity of the colonic lining.
Adequate butyrate oxidation also helps keep the colon environment low in oxygen, which favors the beneficial anaerobic bacteria that produce it, a self-reinforcing loop tied to fiber intake.
Tight junctions and HDAC inhibition
Butyrate supports the proteins that seal the spaces between epithelial cells, the tight junctions, and acts as a histone deacetylase (HDAC) inhibitor, an epigenetic effect that influences gene expression involved in cell differentiation and inflammation in laboratory studies.
This is general educational information, not medical advice. Much of the detailed mechanism comes from cell and animal models; while feeding the fiber that yields butyrate is well supported, oral butyrate supplements are not an established treatment for gut disease, and clinical questions should go to a qualified professional.