Gamma-Glutamyl Transferase (GGT) is an enzyme found primarily in the liver, kidneys, and pancreas. It plays a crucial role in the metabolism of glutathione, a powerful antioxidant, and helps in the transfer of amino acids across cell membranes. Elevated levels of GGT in the blood can indicate liver disease, bile duct obstructions, or excessive alcohol consumption. Testing for GGT is often part of liver function tests, which assess overall liver health. Normal GGT levels vary by age and sex, and results should be interpreted alongside other tests and clinical findings to provide a comprehensive view of liver function and health.