Understanding Your Liver Test Results: What Your Numbers Mean
Just got your liver test results and feeling confused? You're not alone. Liver blood tests can be hard to understand, but they give important clues about your liver health. This guide explains what each number means in simple terms.
Written by Dr. Nimzing Ladep, Consultant Gastroenterologist with 20 years of experience
Section 1: Introduction
What is Liver Function Test?
A liver function test (also called LFT or liver panel) is a blood test that checks how well your liver is working. Your doctor might order this test if:
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You feel tired all the time
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Your skin or eyes look yellow
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You have belly pain
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You're taking medicines that can affect the liver
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You drink alcohol regularly
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You're overweight or have diabetes
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It's part of a routine health check
The test measures different substances in your blood. These substances are made by your liver or affected by how well your liver works.
Section 2: Tests Explained
The Main Liver Tests Explained
ALT (Alanine Aminotransferase)
What it is:
An enzyme (a type of protein) found mainly inside liver cells.
Normal range:
Usually 7-56 units per liter (U/L), but this can vary between laboratories.
What it means when it's high:
When liver cells are damaged, ALT leaks into your blood. High ALT often means your liver cells are being hurt. Common causes include:
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Fatty liver disease (extra fat in the liver)
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Hepatitis (liver inflammation from viruses or other causes)
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Some medicines
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Drinking too much alcohol
⚠️ Should you worry?
A slightly high ALT (less than 2 times normal) is common and often improves with lifestyle changes. Very high levels need quick attention from your doctor. That being said, an abnormal elevation of ALT will often be investigated by your doctor.
AST (Aspartate Aminotransferase)
What it is
Another enzyme found in liver cells, but also in other organs like your heart and muscles.
Normal range:
Usually 10-40 U/L
What it means when it's high:
Like ALT, high AST can mean liver damage. But because AST is also in other organs, doctors look at it together with ALT.
The AST/ALT ratio:
Your doctor might compare these two numbers:
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If AST is higher than ALT (ratio above 2): Often seen with alcohol-related liver damage
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If ALT is higher than AST (ratio below 1): More common with fatty liver or hepatitis
ALP (Alkaline Phosphatase)
What it is:
An enzyme found in liver cells, especially in the tubes (bile ducts) that carry bile out of your liver.
Normal range:
Usually 44-147 U/L (higher in children and pregnant women)
What it means when it's high:
High ALP often means something is blocking the flow of bile from your liver. This could be:
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Gallstones
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A blocked bile duct
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Some liver diseases
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Bone problems (ALP is also found in bones)
✓ What to do:
Compare with ALT levels. If AST is much higher than ALT, this might suggest alcohol-related liver damage.
⚠️ Should you worry?
If ALP is high but ALT and AST are normal, your doctor might check if it's coming from your liver or your bones by requesting another enzyme called GGT.
GGT (Gamma-Glutamyl Transferase)
What it is: An enzyme found throughout the body, but high levels usually mean liver problems.
Normal range: Usually 9-48 U/L
What it means when it's high: High GGT can be caused by:
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Alcohol use (even moderate drinking)
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Fatty liver
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Bile duct problems
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Some medicines
.
Bilirubin
What it is:
A yellow substance made when old red blood cells break down. Your liver processes bilirubin and removes it from your body.
Normal range:
Usually 0.1-1.2 mg/dL
What it means when it's high:
High bilirubin can cause jaundice (yellow skin and eyes). Causes include:
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Liver not working well
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Blocked bile ducts
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Breakdown of red blood cells too quickly
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Gilbert's syndrome (a harmless inherited condition)
Types of bilirubin:
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Direct (conjugated) bilirubin: Processed by the liver. High levels often mean bile duct problems.
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Indirect (unconjugated) bilirubin: Not yet processed by the liver. High levels might mean the liver isn't processing it well, or red blood cells are breaking down too fast.
Why it's useful:
GGT helps doctors figure out if high ALP is coming from your liver or bones. If both are high, it's likely a liver problem
Albumin
What it is:
The main protein made by your liver. It keeps fluid in your blood vessels and carries important substances around your body.
Normal range:
Usually 3.5-5.5 g/dL
What it means when it's low:
Low albumin can mean:
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Your liver isn't making enough protein (serious liver disease)
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You're losing protein through your kidneys or gut
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You're not eating enough protein
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You have inflammation in your body
Total Protein
What it is:
Measures all proteins in your blood, including albumin and others.
Normal range:
Usually 6.0-8.3 g/dL
What it means:
Abnormal total protein might point to liver, kidney, or immune system problems.
PT/INR (Prothrombin Time / International Normalized Ratio)
What it is:
Measures how long your blood takes to clot. Your liver makes most clotting factors.
Normal range:
INR usually 0.8-1.2
What it means when it's high:
High INR means your blood takes longer to clot. This can happen when:
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Your liver isn't making enough clotting factors (serious liver disease)
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You're taking blood thinners like warfarin
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You have vitamin K deficiency
⚠️ Should you worry?
Low albumin is more serious than high liver enzymes. It means your liver may not be working well and needs medical attention.
Should you worry?
High INR without taking blood thinners is serious and needs quick medical attention.
What Do Abnormal Results Mean?
Slightly High Liver Enzymes (Less Than 2x Normal)
Common causes:
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Fatty liver disease (very common if you're overweight)
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Some medicines (pain relievers, statins, antibiotics)
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Recent heavy exercise
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Viral infections
What to do:
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Talk to your doctor about the cause
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Make lifestyle changes (healthy diet, exercise, lose weight if needed)
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Repeat the test in 3-6 months to see if it improves
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Track your results over time with an app like LiverCheck
Very High Liver Enzymes (More Than 10x Normal)
Possible causes:
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Acute hepatitis (sudden liver inflammation)
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Medicine that's very toxic to your liver
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Blocked bile duct
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Heart or circulation problems affecting the liver
Section 3: Patterns
What to do:
This needs urgent medical attention. Your doctor will likely do more tests and might refer you to a liver specialist.
Pattern Recognition: What Doctors Look For
Doctors don't just look at one number. They look at patterns:
Pattern
High ALT and AST, normal ALP
High ALP and GGT, normal or slightly high ALT/AST
AST much higher than ALT
Low albumin, high bilirubin, high INR
What it Suggests
Liver cell damage (hepatitis, fatty liver)
Bile duct problem (blockage, gallstones)
Possible alcohol-related liver damage
Poor liver function (serious liver disease)
Common Questions About Liver Tests
Can liver tests be wrong?
Sometimes, yes. Many things can affect your results:
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Eating before the test (some tests need fasting)
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Recent heavy exercise
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Some medicines or supplements
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Lab errors (rare)
If results seem unusual, your doctor might repeat the test.
How often should I check my liver tests?
It depends on your situation:
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Healthy adults: Once a year as part of routine check-up
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Fatty liver or mild abnormalities: Every 3-6 months
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Chronic liver disease: Every 3-6 months or as your doctor recommends
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Taking medicines that affect the liver: As often as your doctor says
Can I improve my liver test results?
Often, yes! Many liver problems improve with lifestyle changes:
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Lose weight if overweight: Even losing 5-10% of your body weight can help
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Eat a healthy diet: Mediterranean diet works well for liver health
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Exercise regularly: Aim for 30 minutes most days
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Limit alcohol: Or stop completely if you have liver disease
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Avoid unnecessary medicines and supplements: Some can harm your liver
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Get vaccinated: Hepatitis A and B vaccines protect your liver
When Should You See a Doctor?
Contact your doctor if you have:
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Very high liver enzyme levels (more than 5-10 times normal)
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Yellow skin or eyes (jaundice)
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Dark urine or pale stools
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Severe belly pain
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Unusual tiredness that doesn't improve
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Unexplained weight loss
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Swelling in your belly or legs
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Easy bruising or bleeding
Even if you feel fine, abnormal liver tests need follow-up. Many liver problems don't cause symptoms until they're advanced.
Track Your Liver Health With LiverCheck
Understanding your liver test results is just the first step. Tracking them over time helps you and your doctor spot trends and see if treatments are working.
LiverCheck makes it easy to:
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Record all your liver test results in one place
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See your numbers as easy-to-understand graphs
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Track symptoms and medicines
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Share reports with your doctor
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Get reminders for follow-up tests
Best of all, it's free to download and use.
The Bottom Line
Liver test results can seem confusing, but they're powerful tools for understanding your liver health. Here's what to remember:
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One abnormal result doesn't always mean serious disease
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Patterns matter more than single numbers
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Many liver problems can improve with lifestyle changes
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Regular monitoring helps catch problems early
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Always discuss results with your doctor
Remember: This guide is for education only. It doesn't replace advice from your doctor. If you have questions about your specific results, talk to your healthcare provider.
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TBC
Last updated: Dec 2025| Written by Dr. Nimzing Ladep, MBBS, FRCP, PhD