Gamma-glutamyl transferase (GGT) is an enzyme found in many organs throughout the body, with the highest concentrations in the liver. GGT plays a key role in the metabolism of glutathione, an important antioxidant. It's involved in the transfer of amino acids and peptides across cellular membranes and in glutathione metabolism. Elevated GGT levels are commonly used as a marker for liver damage, particularly in detecting bile duct obstructions and liver diseases related to alcohol consumption....
High GGT levels can be caused by: