Liver Function Test (LFT): Normal Ranges and Abnormal Results

You open your report and see ten results with names such as ALT, SGPT, GGT and indirect bilirubin, and one of them is flagged. The name "liver function test" suggests that the panel shows how well your liver is working. Most of it does not.

This guide explains what each marker measures, the normal ranges Intel Lab reports, what the common abnormal patterns point towards, and what a result cannot tell you.

Important: This article is for general education and does not replace medical advice. Laboratory results should always be interpreted by a licensed physician in the context of your individual history and examination.

Start here: an LFT mostly shows liver injury, not liver function

Both the American College of Gastroenterology (ACG) and the British Society of Gastroenterology (BSG) say that the name "liver function test" is misleading.¹² The four enzymes in the panel (ALT, AST, ALP and GGT) rise in the blood when liver cells or bile ducts are injured. They are markers of injury. Only bilirubin and albumin in a standard panel reflect how well the liver is doing its work, together with prothrombin time, which is a separate clotting test.¹²

Three honest points follow from this:

• A normal result does not rule out liver disease. The BSG describes liver blood tests as neither specific diagnostic tools nor specific exclusion tools. Normal results do not rule out advanced fibrosis (scarring) or cirrhosis, and ALT and AST can both be normal in cirrhosis.²
• A bigger number does not always mean a more serious problem. The extent of an abnormal result is not necessarily a guide to its clinical significance. The diagnosis and the context matter more.²
• An abnormal result is a question, not a diagnosis. Liver function tests alone usually cannot diagnose a specific disease, and abnormal results do not always mean there is a problem with the liver.³

What does a liver function test measure?

The Intel Lab Liver Profile reports ten markers from one blood sample.

The profile does not include prothrombin time (INR), which the guidelines list as a marker of liver function.¹² It is not in our online catalog, but the lab can run it on request: contact us.

What are the normal ranges?

Reference ranges differ from one laboratory to another, so always read your result against the range printed on your own report.¹ The table below shows the bands Intel Lab reports for each marker.

Two points help when you read these bands:

• "Normal" for ALT is debated. The ACG argues that a truly healthy ALT is lower than many laboratory ranges allow, and that it differs between men and women.¹ For this reason a physician may take an interest in an ALT near the top of the normal band if you have risk factors for liver disease.
• "Mildly raised" does not mean "safe to ignore". The size of an abnormal result is not a reliable guide to its importance.²

What does a raised ALT or AST mean?

When ALT and AST are raised out of proportion to ALP, physicians call this a hepatocellular pattern. It points to injury of the liver cells themselves.¹ The guidelines list these as common liver causes:¹²

• Fatty liver disease, now called metabolic dysfunction-associated steatotic liver disease (MASLD) and previously called NAFLD⁵
• Alcohol-related liver disease
• Viral hepatitis, including hepatitis B and hepatitis C
• Prescribed medicines, over-the-counter medicines, and herbal or dietary supplements
• Less common conditions such as autoimmune hepatitis and haemochromatosis (iron overload)

When the cause is not the liver

AST and ALT can also rise for reasons outside the liver. The ACG lists skeletal muscle damage, strenuous exercise, thyroid disease and haemolysis (the breakdown of red blood cells) among them. A raised AST with a normal ALT suggests a heart or muscle source.¹ To separate these causes, a physician may request a muscle enzyme such as Creatine Kinase (CPK) or a Thyroid Stimulating Hormone (TSH) test.¹

Fatty liver: what an LFT cannot show

MASLD is fat in the liver in a person who has at least one cardiometabolic risk factor, such as type 2 diabetes or obesity, and who does not drink harmful amounts of alcohol.⁵ A liver function test cannot diagnose fatty liver, and it cannot measure scarring. European guidelines advise a stepwise assessment with blood-based scores such as FIB-4, followed by imaging such as transient elastography.⁵ Intel Lab does not offer liver imaging. If blood sugar is part of your risk, our guide to HbA1c and its normal range explains that test.

What does a raised ALP or GGT mean?

When ALP is raised out of proportion to ALT and AST, the pattern is called cholestatic. It suggests that bile is not flowing freely.¹ Causes include a blocked bile duct and conditions that affect the bile ducts, such as primary biliary cholangitis and primary sclerosing cholangitis.²

ALP does not come only from the liver

Bone is the most common source of ALP outside the liver. Levels are naturally higher in children because of bone growth, in pregnancy because the placenta produces ALP, and in older people, especially women over 50.¹ When ALP is the only raised marker, the BSG says the most likely explanations are vitamin D deficiency or normal childhood growth.² Our guide to vitamin D deficiency covers that test.

This is where GGT helps. GGT is not found in bone, so a raised GGT alongside a raised ALP points to the liver as the source.² The Liver Profile includes both markers so that this comparison can be made from one sample.

A raised GGT on its own

GGT is most commonly raised by obesity, excess alcohol or medicines.² It is not specific for liver disease, and the ACG advises against using it alone as a screening test when the other liver markers are normal.¹

Bilirubin, albumin and protein: the function markers

Bilirubin

A raised direct bilirubin suggests liver cell disease or blocked bile flow.¹ A raised bilirubin when every other liver marker is normal is different. The most common cause is Gilbert's syndrome, which affects 5 to 8% of the population.² It is an inherited condition that does not damage the liver and usually needs no treatment. It can cause mild yellowing of the eyes or skin that comes and goes, and episodes may follow over-exercising, poor sleep, alcohol or not drinking enough fluids.⁴

Only a physician can decide that Gilbert's syndrome is the explanation. They will first consider other causes, including faster breakdown of red blood cells, particularly if you also have anaemia.²

Albumin

Albumin stays in the circulation for about 3 weeks, so it falls slowly. A low level usually suggests a liver problem that has been present for more than 3 weeks.¹ However, low albumin is common without any liver disease. Other causes include severe infection, inflammatory conditions, kidney disease that leaks protein, poor absorption of nutrients, and protein loss from the gut.²

Total protein and globulin

These two results are not specific to the liver. A physician reads them together with albumin and the rest of your results. If either falls in a low or high band, ask your physician what it means for you.

How to prepare, how long results take, and which option to book

Fasting is recommended for the Liver Profile, but it is not mandatory. An overnight fast of 8 to 12 hours, with plain water allowed, gives the cleanest reading, because ALP can rise after a fatty meal in some people.¹

• Medicines and supplements: tell your doctor about everything you take, including over-the-counter and herbal products. Do not stop any medicine unless your doctor tells you to.³
• Exercise: strenuous exercise can raise AST and ALT.¹ If you trained hard shortly before the test, mention it to the physician who reads your result.
• Collection: the sample is blood. Home collection is available anywhere in Dubai, 7 days a week, from 6am to 10pm, and is included in the package price.
• Results: the Liver Profile has a turnaround of 24 hours, and you receive a physician-reviewed digital report.

Check the contents before you choose. Basic Wellness includes two liver enzymes, not a full liver panel: it has no ALP, GGT, bilirubin or albumin.

Single tests are also available, for example Alanine Aminotransferase (ALT/SGPT) at AED 15 and Gamma Glutamyl Transferase (GGT) at AED 25. These are useful when your doctor has asked for one marker to be rechecked. A single test booked alone carries a collection fee, which is shown before payment, so for the full panel the package is usually the simpler choice.

What to do with your result, and who should test

If every marker is normal

This is reassuring, but it is not proof of a healthy liver.² If you have risk factors or symptoms, discuss them with a physician even when your results are normal.

If a marker is flagged

Do not ignore it, and do not assume the worst. In a UK primary care study described in the BSG guideline, 84% of abnormal liver blood tests were still abnormal when repeated one month later.² Waiting for the number to settle is therefore not a plan. Both guidelines expect a physician to look for the cause, starting with your medicines and supplements, alcohol intake and metabolic risk factors, and often a repeat or clarifying test.¹²

For adults, the BSG lists a standard set of next investigations: an abdominal ultrasound, hepatitis B surface antigen, hepatitis C antibody, autoantibodies, immunoglobulins, and ferritin with transferrin saturation, with a full blood count if one has not been done recently.² If your physician requests them, Intel Lab offers Hepatitis B Surface Antigen (HBsAg) at AED 55, Hepatitis C Antibody (Anti-HCV) at AED 75, Ferritin at AED 55 and Complete Blood Count (CBC) at AED 35. Our guide to STD testing in Dubai explains hepatitis B and C testing and confidentiality. Immunoglobulins and prothrombin time (INR) are not in our online catalog, but the lab can run them on request: contact us. Intel Lab does not offer ultrasound, so your physician will arrange that elsewhere.

When not to wait for a routine test

Symptoms of liver disease include yellowing of the skin or eyes, dark urine or pale stools, swelling or pain in the abdomen, swelling in the ankles and legs, frequent itching, nausea, loss of appetite and unusual tiredness.³ Unexplained jaundice needs immediate medical assessment.²⁴ If you have these symptoms, see a doctor promptly instead of booking a home test.

Who should consider testing

Liver function tests are often part of a routine checkup. They are also used for people with a family history of liver disease, obesity, diabetes, heavy alcohol use, hepatitis or exposure to hepatitis, and for people who take medicines that can affect the liver.³ European guidelines also advise looking for liver disease in people with type 2 diabetes, or with obesity and other metabolic risk factors.⁵ How often to repeat the test depends on your risk factors and your earlier results, and is a decision for your physician.

Book a liver function test in Dubai

The Liver Profile measures all 10 markers in this guide for AED 89, with results in 24 hours and home collection in Dubai included. If you are not sure which test fits your situation, ask a clinician first.

This article is for general education and is not a substitute for medical advice. Yellowing of the skin or eyes needs prompt medical assessment and should not wait for a routine blood test. Intel Lab Diagnostics is licensed by the Dubai Health Authority (licence 0046381) and accredited by EIAC to ISO 15189:2022. Prices and turnaround times were verified on 12 November 2026.