Liver and pancreas · Blood

ASAT

An enzyme from the liver, heart and muscles that, together with ALAT, shows whether liver cells are damaged and how severely.

At a glance

Measured in blood
In 13 test panels
No special preparation

Explanation

ASAT: what is measured?

ASAT (aspartate aminotransferase) is an enzyme found in liver cells, but also in heart and skeletal muscle and in red blood cells. When these cells are damaged, ASAT enters the blood. Because ASAT does not come only from the liver, the value is almost always assessed together with ALAT: ALAT is more specific for the liver, while ASAT says something about the severity and helps in finding the cause. The ratio between ASAT and ALAT gives a clue: in fatty liver disease and viral hepatitis, ALAT is usually higher than ASAT; in alcohol-related damage and advanced liver disease, it is often the other way around.

What can it detect?

Damage to liver cells, together with ALAT
A clue that alcohol is the cause: ASAT higher than ALAT
Damage to muscle tissue, for example after heavy exercise or with a muscle disease (creatine kinase is the better test for this)

Result

What does the result mean?

ASAT too high

A raised ASAT together with a raised ALAT fits damage to the liver cells, with the same causes as for ALAT: fatty liver disease, alcohol, viral hepatitis, medicines. If ASAT is raised while ALAT is normal, the enzyme often comes not from the liver but from the muscles: after heavy exercise or strength training, after a fall or muscle injury, with a muscle disease or with a heart attack. A sample in which red blood cells have broken down (hemolysis), for example after a difficult blood draw or a finger prick, also gives a falsely raised ASAT. Anabolic steroids raise both ASAT and ALAT. Symptoms that go with liver damage: tiredness, pain in the upper right abdomen, dark urine, jaundice.

ASAT too low

A low ASAT has no significance. The value can be somewhat lower during pregnancy, with kidney dialysis and with a vitamin B6 deficiency, but the test is not used for that.

After an abnormal result

The GP assesses ASAT together with ALAT and, if a muscle cause is suspected, requests creatine kinase. With a raised ASAT and ALAT without a clear cause, a repeat measurement follows after about 4 weeks without alcohol and after reviewing medicines; if the value stays raised, testing for hepatitis B and C and iron overload follows, and usually an ultrasound of the liver.

Reliability

How reliable is the test?

ASAT is less specific for the liver than ALAT: muscle and heart cells also contain a lot of ASAT. The Dutch GP guideline (NHG) uses ALAT as the first liver test and ASAT mainly as an addition to assess the severity and the possible cause (alcohol, muscle). Apart from ALAT and creatine kinase, a slightly raised ASAT is hard to interpret and often temporary.

What can affect the result?

Heavy exercise, strength training or a muscle injury in the days before the blood draw raises ASAT; an injection into a muscle can do so too.
Hemolysis in the tube (red blood cells broken down by a difficult blood draw, a tourniquet left on too long or a finger prick) gives a falsely raised value.
Alcohol, medicines (including high-dose paracetamol, statins, antibiotics), anabolic steroids and supplements can raise the value.
Reference values differ between laboratories; only compare results from the same laboratory.

Who it is for

Who is the test useful for?

Useful for

Useful as an addition to ALAT when a liver condition is suspected, with long-term heavy alcohol use (the ratio with ALAT then helps), with use of anabolic steroids or medicines that strain the liver, and to monitor a previously abnormal value. As a single test without ALAT, ASAT has little value. In strength athletes, a slightly raised ASAT is often muscle-related; in that case, preferably have blood drawn 2 to 3 days after the last heavy training session.

How common is it?

A slightly raised ASAT without symptoms is usually the result of fatty liver disease, alcohol or muscle strain. According to the Dutch GP guideline (NHG), fatty liver disease occurs in about 1 in 4 adults, and much more often in people with overweight or diabetes. Excessive alcohol use occurs in about 5 to 6 in 100 adults in the Netherlands, about twice as often in men as in women.

NHG guideline on viral hepatitis and other liver conditions; VZinfo (RIVM), Alcohol use among adults 2025

Drawbacks and risks

An ASAT that is raised on its own after exercise or due to hemolysis is easily mistaken for a liver problem.

Get tested

ASAT: test panels

ASAT is part of these test panels. You order online and have your blood drawn at a collection point or collect the sample at home.

Blood draw
AST (GOT)
AST; liver and muscle enzyme.
€ 8,00
Blood draw
Bodybuilder Test
Panel for strength and muscle development; hormones, liver, and muscles.
€ 134,00
Blood draw
InsideTracker
InsideTracker Blood Analysis: analyze 48 biomarkers for complete health optimization and personalized recommendations.
€ 335,00
Blood draw
Testosterone Replacement Therapy (TRT)
Testosterone, LH, FSH, Oestradiol, Prolactin, liver function, and blood values. For men with low testosterone or TRT monitoring.
€ 175,00
Blood draw
Hormone Recovery (After Steroids)
Testosterone, free testosterone, SHBG, LH, FSH, estradiol, TSH, liver function, and lipid profile. For recovery after anabolic steroid use.
€ 325,00
Blood draw
Endurance Sports
Complete blood count, iron status (ferritin, transferrin), kidney function, liver function, testosterone, and hs-CRP. For athletes and endurance sport participants.
€ 203,00
Blood draw
General Blood Test (Basic)
Hemoglobin, MCV, TSH, fT4, eGFR, creatinine, ALT, AST, sodium, and potassium. General health check of kidney, liver, and thyroid.
€ 125,00
Blood draw
Comprehensive Blood Test
Comprehensive blood test covering blood count, thyroid, kidney and liver function, glucose, inflammation markers and cholesterol.
€ 215,00
Blood draw
Liver
ALT, AST, Gamma-GT, alkaline phosphatase, and bilirubin. Assesses liver health in cases of alcohol use, medication, or liver complaints.
€ 58,00

How reliable is the test?

ASAT