Jejunoileal BypassHyperlipidemiasOverweightCholesterolCholesterol, DietaryCholesterol, HDLCholesterol, LDLObesityCholesterol EstersBody Mass IndexCholesterol OxidaseCholesterol 7-alpha-HydroxylaseLipidsTriglyceridesBody WeightCholesterol, VLDLLipoproteinsHypercholesterolemiaRisk FactorsThinnessAnticholesteremic AgentsWeight LossSterol O-AcyltransferaseLipoproteins, HDLPrevalenceSterolsCross-Sectional StudiesHydroxymethylglutaryl CoA ReductasesApolipoprotein A-IDietBile Acids and Salts