OBJECTIVE This study was designed to elucidate the effect of cholecystectomy, a common surgical procedure, on the concentrations of plasma lipids and lipoproteins. METHODS 19 consecutive patient with symptomatic gallstone disease and emptying gallbladder, and 16 control patients (Nissen-Rosetti fundoplication) were studied. Cholesterol, triglyceride, and protein concentrations of various lipoproteins were analysed. RESULTS Plasma total and LDL cholesterol levels were significantly reduced in cholecystectomy patients (p = 0.0048 and p=0.0239) at day 3 after the operation, the values returning to the preoperative level thereafter. In the control patients similar trends were observed for total and LDL cholesterol levels but these changes did not reach statistical significance. In cholecystectomy patients a significant increase was noticed in the very-low-density lipoprotein and intermediate density lipoprotein apoprotein B concentration three years after surgery (p= 0.0019 and p=0.0001). CONCLUSIONS These minor changes in plasma lipoproteins following cholecystectomy are unlikely to have any importance in the development coronary heart disease. They indicate, however, altered enterohepatic metabolism of cholesterol after the removal of the gallbladder.