Alanine aminotransferase, ALT, is a predictor of hepatocellular injury, primarily in the liver cytoplasm, and is elevated especially in the early stages of hepatocellular injury. This damage includes fatty liver, and if fat cells are deposited in the liver later, it will affect ALT elevation, only the range of ALT elevation is not as high. ALT elevation can also be seen with medications, some of which may cause damage to the individual and can cause elevation if taken. Basic ALT elevation reflects the degree of liver damage. Whatever the cause of liver damage, ALT will be elevated, including fatty liver and alcoholic liver. Long-term alcohol use can also cause liver cell damage, which gradually leads to cirrhosis or other adverse outcomes, and elevated transaminases. So alcoholic liver, fatty liver, viral hepatitis, drug-related injury, as long as the liver cells are damaged, the ALT concentration in the blood will be elevated, and the abnormal indicators can be seen in clinical blood sampling. Once the cause is found, appropriate interventions are made to bring it back to normal levels as much as possible.