Gallbladder bile composition in different ethnic groups.
A total of 194 gallbladder biles from various ethnic groups were analyzed for their composition. The solubility of cholesterol in bile was determined mainly by its relative amounts of phospholipid and bile salt present. Bile from patients with gallstones was usually supersaturated with cholesterol above the boundary of the metastable state. Biles from normal white subjects of Finland, New Zealand, and the United States were already in the metastable state of supersaturation with cholesterol. The Masai of East Africa and black subjects of the Unites States had a bile level below the limit of maximum cholesterol solubility. This study indicates that the difference in the prevalence of cholesterol cholelithiasis in various ethnic groups was related to the difference in their bile compontified factors.