A low alanine aminotransferase is a sign of a healthy liver. Alanine aminotransferase is found mainly in liver cells, and the normal range in serum is 0-35 U/L by colorimetric assay and 6-24 U/L by continuous monitoring. Elevated levels are usually due to damage to the liver cells, and low levels are usually due to a healthy liver. When the liver is healthy, it will accommodate most of the alanine aminotransferase, so that the serum alanine aminotransferase content is very small or even tends to 0. Without the overflow of alanine aminotransferase from the liver, the serum alanine aminotransferase test value will certainly be on the low side, which indicates that the patient’s liver should be healthy, and is not generally regarded as a pathological phenomenon, which is generally not hazardous to the human body.