| Marker | Gabriel optimal | Typical lab range | Functional range |
|---|---|---|---|
| AST | 10 to 26 U/L | 40 or lower | 10 to 26 |
What AST measures
AST is an enzyme that helps cells process amino acids. It is reported in units per liter (U/L) and usually comes as part of a comprehensive metabolic panel (CMP) or a liver panel.
You may see it labeled AST, SGOT (serum glutamic-oxaloacetic transaminase) or aspartate transaminase. They are the same test.
Unlike ALT, which sits mostly in the liver, AST is spread across the liver, skeletal muscle, heart, kidneys, pancreas and red blood cells. So a high AST tells you some cells are releasing it, but not on its own which ones.
What a high AST can mean
Common causes of a raised AST:
- Intense exercise or muscle injury. Heavy lifting, long runs or a fall can raise AST for a while, and so can muscle conditions. ALT often rises less.
- Fatty liver. Usually with ALT higher than AST.
- Alcohol. Heavy drinking raises AST, often more than ALT.
- Medications and supplements that stress the liver, including acetaminophen.
- Hepatitis and other liver conditions, including cirrhosis and iron overload (hemochromatosis).
- Other sources: a recent heart attack or heart procedure, pancreatitis, mononucleosis, burns, seizures and surgery. A blood sample that was handled roughly can also read high, because red cells contain AST.
AST to ALT ratio: the basics
Clinicians often divide AST by ALT. The ratio gives a direction to look, never a diagnosis on its own:
| Pattern | What it can point toward |
|---|---|
| AST lower than ALT (ratio below 1) | The usual pattern with fatty liver |
| AST about twice ALT or more (ratio above 2) | Can point toward alcohol-related liver injury |
| AST high, ALT normal or slightly high | Often muscle, especially after exercise; a creatine kinase (CK) test helps tell |
What to do with a high result
- Look at ALT and the rest of the panel. If ALT is normal, muscle is a common explanation. If both are up, the liver is more likely involved.
- Think about the days before the draw. Hard workouts, a new medication or supplement, and alcohol all matter. Tell your clinician.
- Ask whether a creatine kinase (CK) test makes sense if you exercise hard or have muscle aches.
- Recheck after a few easy days. AST can shift from one draw to the next, so confirm a borderline value before acting on it.
See a clinician promptly if a high AST comes with chest pain, yellowing of the skin or eyes, dark urine, pain in the upper right belly, severe muscle pain or weakness with dark cola-colored urine, or confusion.
Common questions
What is SGOT in a blood test?
SGOT is the older name for AST, an enzyme found in the liver, muscles, heart and other tissues. SGOT and AST are the same test.
What is a normal AST level?
Many labs flag AST above about 35 to 40 U/L, and ranges vary by lab. Gabriel's optimal range is 10 to 26 U/L.
Can working out raise AST?
Yes. Intense exercise releases AST from muscle, sometimes enough to read high for a while afterward. A retest after a few easy days often comes back lower.
What does it mean if AST is higher than ALT?
It can mean the AST is coming from muscle, or it can point toward alcohol-related liver injury when AST is about twice ALT or more. Your clinician reads the ratio with your history and other tests; it does not diagnose anything on its own.
Is a low AST a problem?
Usually not. Low AST is generally considered normal.
Sources
- AST Test MedlinePlus, U.S. National Library of Medicine
- Aspartate Transferase (AST) Cleveland Clinic
- Mildly Elevated Liver Transaminase Levels: Causes and Evaluation (Oh et al., 2017) American Family Physician
- ALT Blood Test MedlinePlus, U.S. National Library of Medicine
- Laboratory Tests of the Liver and Gallbladder Merck Manual Professional Edition
This guide is general information, not medical advice. It does not replace a visit with a licensed clinician. Gabriel membership is not health insurance.