Is an alanine aminotransferase (ALT) level of 6 too low?

　　An ALT (alanine aminotransferase) level of 6 U/L falls within the normal range and is not abnormally low, so there is no need for excessive concern. This indicator primarily reflects hepatocyte damage, with a typical reference range of 0–40 U/L. A value of 6 U/L lies well within this interval and has no clinical or pathological significance. However, if accompanied by other physical discomforts or abnormal test results, timely medical evaluation and further relevant examinations are recommended.

　　A low ALT level is usually related to physiological factors or testing errors. Long-term vegetarian diets or insufficient protein intake may lead to a lack of substrates required for hepatic enzyme synthesis, resulting in values at the lower end of the normal range. Additionally, improper sample collection or instrument calibration errors during testing may also cause falsely low results, which are generally temporary.

　　In rare cases, markedly decreased ALT levels may be associated with advanced chronic liver disease or hypothyroidism. However, these conditions are typically accompanied by obvious symptoms such as jaundice, fatigue, and cold intolerance, along with concurrent abnormalities in other laboratory indicators. Therefore, an isolated ALT value of 6 U/L does not warrant consideration of such pathological causes.

　　Maintain a balanced diet with adequate intake of high-quality proteins and fresh fruits and vegetables, avoiding extreme dieting or prolonged vegetarianism. Follow a regular sleep schedule without staying up late, engage in moderate aerobic exercise, maintain a positive mood, avoid misuse of medications, reduce hepatic burden, and support normal metabolic function.