Gamma-Glutamyl Transferase (GGT)
Disclaimer: Information on this page is for educational purposes. Consult a physician to interpret your test results. Health Vault helps track biomarker trends but does not replace medical advice.
What This Test Measures
GGT is an enzyme linked to biliary ducts and liver. Sensitive to cholestasis and alcohol-related injury.
Elevated GGT with normal ALP may indicate alcoholic or drug-induced liver injury.
GGT also rises with obesity and metabolic syndrome independent of liver disease.
Normal Ranges
| Group | Reference Range |
|---|---|
| Men | 0–55 U/L |
| Women | 0–38 U/L |
| Children | 0–50 U/L |
Reference ranges may vary by laboratory and assay method.
Causes of High Levels
- Alcoholic liver disease
- Cholestasis
- Drug-induced liver injury
- Pancreatitis
- Obesity and metabolic syndrome
Causes of Low Levels
- Rarely clinically significant
Test Preparation
- Fasting preferred
- Avoid alcohol for at least 72 hours
- Report all medications
Related Biomarkers
| Biomarker | Relationship |
|---|---|
| Alkaline Phosphatase | Cholestasis panel |
| Alanine Aminotransferase (ALT) | Hepatocellular injury |
| Direct Bilirubin | Obstructive jaundice |
FAQ
How often should I take this test?
With liver disease — every 3–6 months.
What should I do if my result is abnormal?
Elevation with alcohol use — abstinence and repeat testing in 4–8 weeks.
Last updated: June 2026