AST (aspartate transaminase) and ALT (alanine transaminase) are enzymes found in the liver that help convert proteins into energy for the liver cells. They are also present in muscles and other organs in the body. When liver cells are damaged, they release AST and ALT into the bloodstream, causing an increase in their levels.
An AST blood test measures the amount of AST in the blood, while an ALT blood test measures the amount of ALT in the blood. These tests are commonly used to help diagnose liver damage or disease, as well as monitor liver problems.
Normal levels of AST and ALT in the blood are usually low. Elevated levels of these enzymes may indicate liver damage, disease, or muscle damage. The interpretation of elevated AST and ALT results depends upon the entire clinical evaluation of an individual, and so it is best done by physicians experienced in evaluating liver disease and muscle disease.
The AST/ALT ratio is a comparison of the levels of the two enzymes. This measurement can point to liver diseases, but only if the enzyme levels are significantly elevated. A typical AST/ALT ratio would be less than 1.
If persistent increments in AST and ALT levels are observed without any visible health issues, it’s best to consult a professional gastroenterologist for further evaluation. Lowering AST and ALT levels can be achieved by changing lifestyle habits, such as regular exercise, which would improve insulin sensitivity and reduce liver inflammation.
