Lithocholic Acid Unit Converter

Lithocholic acid (LCA) is a secondary bile acid produced when bacteria in the colon convert the primary bile acid chenodeoxycholic acid (CDCA) through a process called 7α-dehydroxylation.

It is the most hydrophobic of the common bile acids and circulates in very small amounts in the blood. Normal serum levels are ≤0.09 µmol/L. Because it is potentially toxic at high concentrations, the liver actively detoxifies LCA through sulfation and hydroxylation before excreting it in bile and feces.

Measuring lithocholic acid as part of a bile acid profile helps evaluate the health of the enterohepatic circulation, which involves the liver, bile ducts, intestine, and portal blood flow.

Lithocholic acid is produced in the colon by specific families of gut bacteria (primarily Lachnospiraceae, Oscillospiraceae, and Ruminococcaceae) that remove a hydroxyl group from the primary bile acid chenodeoxycholic acid. The liver then partially recirculates it through the enterohepatic cycle, sulfating and hydroxylating LCA to limit its toxicity.