ALT
ALT (alanine aminotransferase) is an enzyme contained in liver cells. When they are stressed or damaged it leaks into the blood, making it the most sensitive and most liver-specific routine indicator of liver stress.
| Rating | Range | What it means |
|---|---|---|
| Good | below 33 U/L | Liver with no signs of strain. |
| Worth improving | 33 – 50 U/L | Slightly elevated — often fatty liver; lifestyle. |
| Talk to a doctor | 50 U/L and above | Elevated — check your liver; seek advice. |
This marker also has 2 age- or sex-specific range sets in the app — the table shows the general one.
Why it matters
EASL: an elevated level indicates liver strain (fatty liver, alcohol, viruses, medications).
If it’s low
Low ALT has no clinical significance.
If it’s high
Elevated ALT means the liver cells are under stress. The most common cause here is fatty liver (metabolic, manageable); the value often falls nicely with a change in lifestyle.
What to do
Today, no alcohol or sugary drinks, and add a walk. For fatty liver, weight loss (≥7–10 %) and physical activity help most. Do not measure right after intense exercise.
Read together with
AST · GGT · Bilirubin (total) · Triglycerides
Part of the guide: Liver →
Articles about this marker
- Albumin blood test: what low or high albumin meansMarker explained
- Alkaline phosphatase (ALP): what high or low levels meanMarker explained
- Blood biomarkers of metabolic health: what to measure and whyMetabolic health
- Blood chemistry tests: normal values for ALT, AST, GGT, CRP, CK, creatinine and glucoseReading your report
- Blood test reference values — table by test for adultsReading your report
- Fatty liver: what raised liver enzymes mean and what FIB-4 isLiver
This content is for information only and is not a substitute for medical advice. Talk to your doctor about your results.
Your number, not the average
Upload your report: we rate your exact value for your age and sex, show the source, and tell you what to do next.