Cholesterol gallstones are made up of:-

1. Cholesterol stones: Contains >50% of crystalline cholesterol monohydrate 2. Pigment stones: Composed of bilirubin & calcium salts predominantly Risk Factors for Gallstones Cholesterol Stones Demography: nohern Europeans, Noh and South Americans, Native Americans, Mexican Americans Advancing age Female sex hormones Female gender Oral contraceptives Pregnancy Obesity and metabolic syndrome Rapid weight reduction Gallbladder stasis Inborn disorders of bile acid metabolism Hyperlipidemia syndromes Pigment Stones Demography: Asians more than Westerners, rural more than urban Chronic hemolytic syndromes Biliary infection Gastrointestinal disorders: ileal disease (e.g., Crohn disease), ileal resection Or bypass, cystic fibrosis with pancreatic insufficiency.