Alanine transaminase (ALT) is an enzyme primarily found in the liver. It plays a crucial role in amino acid metabolism by facilitating the conversion of alanine and alpha-ketoglutarate into pyruvate and glutamate. This process is essential for energy production and the synthesis of proteins. ALT levels in the blood can indicate liver health. Elevated levels may suggest liver damage or disease, such as hepatitis or fatty liver disease. Routine blood tests often measure ALT to help diagnose and monitor liver conditions, making it an important marker in medical assessments.