What is the normal value of alanine aminotransferase?
Aug 26, 2025
Source: Cainiu Health
Dr. Liu Feng
Introduction
From a common perspective of test results, when the values are within the reference range, it indicates that liver cells have not sustained significant damage, and alanine aminotransferase (ALT) within liver cells has not been largely released into the bloodstream. The liver's metabolic function is in a normal condition. In such cases, no special treatment is required; maintaining a regular healthy lifestyle is sufficient.
Under normal circumstances, the reference range for alanine aminotransferase (ALT) is generally between 0-40 U/L. Some testing institutions may have slightly different reference ranges due to variations in reagents or instruments; therefore, the values indicated on the test report should be considered definitive. Detailed analysis is as follows:
From a common perspective of test results, when the value falls within the reference range, it indicates no significant damage to liver cells. The alanine aminotransferase within liver cells hasn't been largely released into the bloodstream, suggesting normal liver metabolic function. No special treatment is required in such cases, and maintaining regular healthy lifestyle habits is sufficient.
Regarding possible causes of abnormal values, if the value exceeds the reference range, it may be due to short-term late-night activities, heavy alcohol consumption, strenuous exercise, or taking certain medications. In such cases, the elevation is often temporary and may return to normal after adjusting lifestyle habits or discontinuing medications and retesting. Alternatively, it could be caused by liver diseases such as hepatitis, fatty liver, or cirrhosis. At this time, symptoms such as fatigue and decreased appetite are usually present, so further examinations are necessary to determine the specific cause.
Routinely, regular physical examinations should be conducted to monitor changes in this indicator. If abnormal values are detected along with physical discomfort, medical attention should be sought promptly to complete relevant examinations and avoid delays in intervention that could affect health.
