Fasting postprandial metabolism

In the immediate postprandial metabolism, carbohydrate is the preferred source of energy. After 12-15 h of fasting, fat is used as the energy source. 

Disturbances of Bile Acid Metabolism in Hepatocellular Disease. Fasting plasma bile acid concentrations are elevated in hepatocellular diseases, such as hepatitis and cirrhosis. The mechanisms responsible are regurgitation of bile acids from cholestatic hepatocytes and portosystemic shunting. These defects allow the plasma concentrations to rise proportionately much higher than normal following meals, suggestmg that the postprandial rise in plasma bile acids may be a sensitive test for the detection of liver disease. 

Reznik Y, Morello R, Pousse P, Mahoudeau J, and Fradin S, The effect of age, body mass index, and fasting triglyceride level on postprandial lipemia is dependent on apolipoprotein E polymorphism in subjects with non-insulin-dependent diabetes mel-litus. Metabolism, Sep 2002 51(9) 1088-1092. 

However, postprandial hyperinsulinemia is independently associated with CAD irrespective of fasting glucose, postprandial glucose, and fasting insulin levels in nondiabetic women with clustering of factors of the metabolic syndrome (78). 

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