Beta-glucan–bile acid interaction

Beta-glucan is a soluble dietary fiber found primarily in oats, barley, and certain mushrooms. When consumed, it forms a viscous gel in the gut that binds bile acids, reducing their reabsorption in the small intestine[1][3][7]. This results in increased excretion of bile acids in feces and compels the liver to convert more cholesterol into bile acids, thereby lowering LDL cholesterol levels in the blood[1][3][5][7]. This mechanism is well established, though "LDL cholesterol absorption/reduction via beta-glucan binding bile acids" is not a single molecular target or receptor but rather describes the overall physiologic effect[3][5][7]. Beta-glucan's cholesterol-lowering efficacy is influenced by its molecular weight, source, and concentration, as well as its impact on gut microbiota and resultant short-chain fatty acid production[2][7].

Other names

Beta-glucan bile acid sequestrationBeta-glucan–mediated cholesterol reductionDietary fiber–bile acid binding

Physical binding of bile acids by viscous beta-glucan in the gut, impeding their reabsorption[3][7]. Enhanced fecal bile acid excretion requires the liver to synthesize new bile acids from cholesterol, which reduces systemic LDL cholesterol[7]. Increased intestinal viscosity by beta-glucan, decreasing cholesterol and fat absorption[5][8]. Fermentation of beta-glucan by gut microbiota generates short-chain fatty acids, which may also lower cholesterol[1][7].