Educational information only. At Precursor, blood testing is requested and reviewed by a clinician and considered alongside your history and other markers, not as a stand-alone diagnosis. Testing is performed in NATA-accredited laboratories to ISO 15189 standards.

What is AST?

AST, or aspartate aminotransferase, is an enzyme found in the liver but also in muscle, heart and red blood cells. Like ALT, it is released when cells are damaged. Because it is less specific to the liver, AST is most useful read together with ALT, where the pattern between them offers clues about the source.

Why it matters

AST complements ALT. The ratio between the two can help point toward particular causes of liver strain, and because AST also comes from muscle, a raised level is occasionally a clue to something outside the liver entirely, such as recent intense exercise.

What your results can mean

Higher than optimal

A raised AST can reflect liver-cell stress, but also muscle or other sources. Its meaning is clearest when compared with ALT and the rest of the liver panel.

Within the healthy range

An AST in range, alongside a normal ALT, is reassuring for liver-cell health.

Reference ranges in Australia

AST is reported in units per litre (U/L), with laboratory-specific reference ranges. Read your result against the range on your own report and, importantly, alongside your ALT.

Test your liver with Precursor

AST is most meaningful paired with ALT. At Precursor it is measured as part of Full Advanced Bloods, a single clinician-reviewed blood draw covering your liver, heart, metabolic, hormonal, kidney, thyroid and nutrient markers together, giving you and your clinician a broad baseline to understand and track.