Influence of fat-rich versus carbohydrate-rich diets on bile acid kinetics, biliary lipids, and net steroid balance in hyperlipidemic subjects.

Altogether, 14 patients with hyperlipoproteinemia type IIA (n = 3), IIb (n = 4), or IV (n = 7) were maintained on diets in which 60% of the energy was supplied as fat or carbohydrates. The switch from the fat-rich to the carbohydrate-rich diet resulted in elevation of the plasma triglyceride levels. Although not consistent in all instances, the change of diet also resulted in an enhanced formation of both cholic acid and chenodeoxycholic acid and a higher contribution of deoxycholic acid in duodenal bile. Due to a reciprocal decrease in the excretion of neutral steroids in feces, the mean steroid balance remained unchanged. In all but four patients this switch of diets was associated with a decreased molar cholesterol concentration in duodenal bile obtained in the postabsorptive state.