Screening for Elevated Liver Enzymes

Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) are enzymes located in liver cells that leak out into circulating blood when liver cells are injured.

ALT and AST are found in other cells in the body, but their concentration is highest in liver cells. ALT and AST are also found in heart, skeletal muscle, and red blood cells. Elevated levels of ALT and AST in the blood indicate some type of liver damage or injury. 

What you can learn

This liver enzymes screening is a simple way for you to learn if your ALT and AST liver enzyme levels are in the normal range or if they are elevated, suggesting possible liver damage. We encourage you to share your results with your physician.

Male¹     Low Normal Range1 Elevated

ALT 0-18.72 U/L 18.73 to 27.35 U/L >27.35 U/L AST 0-37.88 U/L 37.89-54.87 U/L >54.87 U/L

Female¹     Low Normal Range1 Elevated

ALT 0-12.98 U/L 12.99-16.53 U/L >16.53 U/L AST 0-32.52 U/L 32.53-42.37 U/L >42.37 U/L

¹ Life Line Screening established references ranges based on data from 22,163 patients.

Who should have a liver enzymes screening

Moderate elevations in ALT and AST (less than 5 times the upper normal limit), in a person without any symptoms could be caused by viral hepatitis, excessive alcohol, medication, fatty liver or cirrhosis (scarring in the liver) among other things. 
This test is also recommended if you have just started taking statin drugs to lower elevated cholesterol levels.  

How to prepare

There is nothing you need to do in advance for this screening. This test does not require fasting beforehand.