Human Biochemistry Volume 1 - Murray R. 1993

Bioenergetics and Metabolism of Carbohydrates and Lipids
Synthesis, Transport, and Excretion of Cholesterol
Cholesterol Elimination and Bile Acid Salt Formation

About 1 g of Cholesterol is eliminated from The Human Body daily. Approximately half of this amount is excreted in the feces after being converted into Bile acids. The remaining portion is excreted as neutral Steroids. Most of the cholesterol secreted into the bile is reabsorbed; it is believed that at least a portion of the cholesterol that serves as the precursor for fecal sterols originates from the intestinal mucosa. The primary fecal sterol is coprostanol, which is formed from cholesterol in the lower intestine through the action of the local microflora. A significant proportion of the bile salts delivered via the bile are absorbed in the intestine and returned to the Liver via the portal vein, where they are re-secreted into the bile. This pathway of bile salt transport is known as the enterohepatic Circulation. The remaining portion of the bile salts and their derivatives are excreted in the feces. Under the action of intestinal Bacteria, primary bile acids are converted into secondary bile acids.



Last update: 06/08/2026

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