ALT (SGPT, Alanine Aminotransferase): What Your Result Means
Result guide · Liver
Content last reviewed 2026-09-12 · Educational information — not medical advice
Quick answer
ALT is the most liver-specific enzyme. Mild elevations most often mean fatty liver disease; marked spikes mean hepatitis or toxin/drug injury. Isolated mild bumps frequently normalize on repeat — trend beats snapshot.
What is ALT (SGPT, Alanine Aminotransferase)?
Alanine aminotransferase lives concentrated inside hepatocytes, leaking into blood when liver cells are irritated or die. Unlike AST (also abundant in muscle/heart), ALT specificity makes it the go-to liver-injury screen. Reference intervals cluster around 7–56 U/L though newer data suggest sex-specific lower cutoffs.
Typical reference interval: Commonly cited upper limit ~40–56 U/L; metabolically healthy cohorts suggest lower true normals (~29 men, ~19 women).. Laboratories differ — the interval printed on YOUR report always governs.
If your ALT (SGPT, Alanine Aminotransferase) is high
Common reasons ALT (SGPT, Alanine Aminotransferase) runs above the reference interval:
- NAFLD/MASLD fatty liver — the Western-world epidemic explanation for mild chronic elevation
- Alcohol — AST>ALT pattern classically, but overlap abounds
- Viral hepatitis — A/B/C — marked elevations, hundreds-to-thousands in acute phases
- Medications and supplements — statins, acetaminophen (especially combined with alcohol), antibiotics, herbal products — green tea extract and bodybuilding supplements increasingly implicated
- Intense exercise — transient enzyme leaks confuse unwary interpretations
- Hemochromatosis, Wilson disease, autoimmune hepatitis, alpha-1 antitrypsin — the inherited/metabolic shortlist when basics exclude
- Celiac disease — occasionally presents purely as unexplained transaminitis
If your ALT (SGPT, Alanine Aminotransferase) is low
Common reasons ALT (SGPT, Alanine Aminotransferase) runs below the reference interval:
- No significance attached — isolated low ALT carries no recognized pathology
- B12/pyridoxine deficiency — rare cofactor-dependent reductions
Symptoms worth knowing
Liver irritation itself often goes unnoticed — fatigue and right-upper-quadrant dullness maybe. Jaundice, dark urine, pale stools, and itching signal deeper dysfunction where OTHER liver markers (bilirubin, INR) also move. ALT rising alone means irritation; ALT rising WITH bilubrin/coagulation derangement means failure territory.
What usually happens next
Get your ALT (SGPT, Alanine Aminotransferase) checked
These lab tests measure ALT (SGPT, Alanine Aminotransferase) directly. Ordering online takes a few minutes and results arrive securely.
We may earn a commission when you order through partner links on the following pages. Educational information here never replaces advice from a qualified healthcare provider.
Panels that include this value
ALT (SGPT, Alanine Aminotransferase) appears as one line inside these broader panels — better value than ordering single markers alone:
Related result guides
Frequently asked questions about ALT (SGPT, Alanine Aminotransferase) results
I worked out hard yesterday — will my ALT be fake-high?
Possibly — vigorous exercise elevates transaminases for days. Serious athletes sometimes schedule liver panels away from leg day.
Can fatty liver ALT normalize?
Yes — weight loss of 7–10% reliably improves ALT and histology. The enzyme tracks the disease's activity well, making it useful progress-monitoring.
Browse all lab tests
Looking for a specific test instead of a result explanation? Our full catalog covers hundreds of lab tests and panels.