From the Guidelines
Elevated GGT (gamma-glutamyl transferase) is a marker that may indicate liver or bile duct damage, and according to the most recent study 1, it is essential to investigate the underlying cause. Elevated GGT means that this liver enzyme is higher than normal in your blood test. Normal GGT levels typically range from 8-61 units/L for men and 5-36 units/L for women, though reference ranges vary by laboratory. GGT is primarily found in liver, bile duct, and kidney cells, and when these tissues are injured or inflamed, the enzyme leaks into the bloodstream. Some common causes of elevated GGT include:
- Alcohol consumption
- Certain medications (like phenytoin, carbamazepine, and barbiturates)
- Fatty liver disease
- Viral hepatitis
- Bile duct obstruction
- Pancreatitis
- Heart failure If you have elevated GGT, your doctor will likely recommend reducing alcohol intake, reviewing your medications, improving diet and exercise habits, and may order additional tests like ALT, AST, alkaline phosphatase, and bilirubin to better understand the cause. As stated in the study 1, measurements of GGT can indicate whether pathologically elevated ALP is of hepatic or nonhepatic origin, and concomitantly elevated GGT can help confirm that an elevated ALP originates from the liver and indicates cholestasis. GGT elevation alone doesn't necessarily indicate serious disease, but it serves as an important marker that warrants further investigation to determine the underlying cause, and high GGT levels have been associated with an increased risk of liver cancer and clinical decompensation events in patients with cirrhosis, as mentioned in the study 1.
From the Research
Elevated GGT Levels
Elevated GGT (gamma-glutamyltransferase) levels can be an indicator of various health issues, including:
- Liver disease, such as alcoholic liver disease, viral hepatitis, and non-alcoholic fatty liver disease 2, 3, 4
- Cholestasis, a condition where bile flow is reduced or blocked 2, 4
- Oxidative stress and antioxidant inadequacy 3, 4
- Increased risk of mortality, incident type 2 diabetes, cardiovascular events, chronic kidney disease, and cancer 5, 3
- Metabolic syndrome and its related disorders 3
Associated Factors
Elevated GGT levels have been associated with various factors, including:
- Alcohol consumption 2, 3
- Certain drugs and medications 2
- Obesity and high body mass index (BMI) 6
- High triglyceride (TG) levels 4, 6
- High total cholesterol (TC) levels 4
- Low-density lipoprotein cholesterol and high-density lipoprotein cholesterol levels 4
Disease-Specific GGT Levels
GGT levels can vary depending on the underlying liver disease, with: