Alanine aminotransferase (ALT) is an enzyme primarily found in the liver. It plays a crucial role in the process of amino acid metabolism, specifically in converting alanine and alpha-ketoglutarate into pyruvate and glutamate. This reaction is important for energy production and the synthesis of various biomolecules. ALT levels in the blood can indicate liver health. Elevated levels may suggest liver damage or disease, such as hepatitis or fatty liver disease. Therefore, measuring ALT is a common practice in routine blood tests to assess liver function and overall health.