How high does gamma-glutamyl transferase (GGT) have to be to be considered severe?

Under normal circumstances, the reference range for gamma-glutamyl transferase (GGT) is 7–45 U/L. Values exceeding this range are considered abnormal: mildly elevated when below 100 U/L, moderately elevated between 100 and 300 U/L, and significantly elevated above 300 U/L, which requires high vigilance. Detailed analysis is as follows:

Mild elevations are often associated with lifestyle factors such as alcohol consumption, staying up late, and a high-fat diet, indicating minor liver damage. The levels usually return to normal spontaneously after timely alcohol cessation, improved sleep patterns, and adopting a light diet. There's generally no need for excessive concern, but regular follow-up tests are recommended to monitor changes.

Moderate elevations may indicate conditions such as fatty liver or drug-induced liver injury, suggesting a certain degree of liver inflammation. Further examinations, such as abdominal ultrasound of the liver and bile ducts, are needed to identify the underlying cause, followed by targeted interventions—such as discontinuing hepatotoxic medications or managing body weight—to prevent disease progression.

A GGT level exceeding 300 U/L indicates a severe increase, commonly associated with diseases like hepatitis, cirrhosis, or biliary obstruction, reflecting significant hepatocellular damage. In such cases, prompt and comprehensive evaluation is necessary, and standardized treatment should be initiated immediately after diagnosis to prevent continuous deterioration of liver function.

The assessment of severity should take into account other liver function parameters and the underlying cause, rather than relying solely on the GGT value. Maintaining a healthy lifestyle, avoiding medication abuse, and undergoing regular health check-ups are essential for protecting liver health.