Liver Function Tests – Understanding Your Results
Your liver does a lot to keep you healthy — it breaks down toxins and helps digestion — but it also produces proteins you can’t live without. So how do you know if your liver is chugging along as it should? These are a series of blood tests used to check liver health by measuring the levels of proteins, enzymes, and other substances that the liver produces or processes.
LFTs are an essential diagnostic tool for diseases of the liver, monitoring treatment and side effects from certain medicines. But just because liver function tests are abnormal doesn’t necessarily mean you have liver disease. At times, they indicate a temporary inflammation, medication usage or other underlying conditions that require further exploration.
What Are Liver Function Blood Tests?
Liver function tests measure levels of certain markers in the blood. These can offer clues about how healthy the liver is functioning and if there is any damage or inflammation.
These are the key ingredients that were tested:
- ALT (Alanine Transaminase): An enzyme that rises when cells in the liver are damaged.
- AST (Aspartate Transaminase): Can be found in the liver and muscles; an increase in AST may indicate liver injury or muscle damage.
- ALP (Alkaline Phosphatase): Elevated alkaline phosphatase levels can indicate bile duct blockage or damage to the liver.
- Albumin & Total Protein: Low levels may suggest liver disorders or poor nutrition.
- Bilirubin: It can be high if you have jaundice and can signal problems with biliary flow or red blood cell breakdown.
- GGT (Gamma-Glutamyltransferase): Commonly increases in biliary tract disease or alcohol-induced liver disorders.
- LD (L-Lactate Dehydrogenase): Will increase with liver, heart, and muscle disturbances.
- PT (Prothrombin Time): Tests how long blood takes to clot — a prolonged PT can indicate liver damage.
Liver Function Test Normal Values
Here’s a general guide to reference ranges (though they can vary slightly by lab):
Test | Typical Range |
ALT | 7 – 56 U/L |
AST | 10 – 40 U/L |
ALP | 44 – 147 U/L |
Albumin | 35 – 50 g/L |
Bilirubin | 0.3 – 1.2 mg/dL |
GGT | 9 – 48 U/L |
PT | 11 – 13.5 seconds |
Note: These ranges are averages. Age, sex, ethnicity, and even time of day can affect results.
Interpreting LFT results must always be done in the context of your overall health, symptoms, and medical history. At Chase Lodge Hospital, our clinicians take a comprehensive approach to ensure accuracy and clarity in your diagnosis.
Reasons for High Liver Function Test Results
If your LFTs return high, a few potential culprits might be the cause:
- Liver conditions: Hepatitis (viral or autoimmune), non-alcoholic fatty liver disease (NAFLD), cirrhosis.
- Medicines and poisons: Medications (both over-the-counter such as paracetamol and prescribed medicines such as statins) and alcohol misuse.
- Bile duct obstruction: Conditions such as gallstones or tumours may block the ducts that channel bile, causing it to accumulate.
- Metabolic diseases: Like Wilson’s disease or haemochromatosis.
- Muscle or heart conditions: AST levels can be affected by these, particularly in heavy physical activity or if you have heart disease.
Usually, doctors assess these factors with more tests or imaging in order to narrow down the cause.
What Does a Liver Function Test Abnormal Result Mean?
LFT abnormalities may vary from mild elevation of markers to abnormal readings. Mildly elevated levels are frequently rechecked, while more serious results are tested to rule out other causes of the problem such as:
- Ultrasound or CT scans
- Liver biopsy
- Specialist referral for chronic liver disease
It’s also a question of acute (short-term) versus chronic (long-standing) liver issues — a difference that can lead to appropriate treatment options.
Why Do I Need a Repeat Liver Function Test?
There are several reasons your doctor might request repeat LFTs:
- To monitor a current liver disease.
- To evaluate progress of treatment or lifestyle adjustment.
- To verify an abnormal result from a previous test.
- To monitor recovery from liver damage, such as damage related to alcohol.
The timing of these tests will vary based on your risk factors, current health status, and whether you are under treatment for a known liver condition.
How to Improve Liver Function Test Results
Taking care of your liver doesn’t have to be complex. Here’s what you can do to lower your risk:
- Eat a liver-friendly diet: You’ll want to eat a diet of whole foods bursting with antioxidants — leafy greens, berries, nuts, and oily fish.
- Bottoms up — not too much: Even moderate drinking can mess with your liver enzymes.
- Eliminate any medications/supplements which put a strain on the liver.
- Keep your weight in check: Obesity is one of the main risk factors for fatty liver disease.
- Get regular exercise: Aim for at least 150 minutes of moderate exercise a week.
- Treat the cause: If it’s hepatitis or a metabolic disorder, follow your treatment regimen closely.
Conclusion
Liver function tests provide a way to check on how well your body is doing (systematic health check) and also to detect liver problems in their earliest stages. Although an abnormal result can feel scary, it doesn’t always indicate the presence of a life-threatening illness — but it does deserve thorough investigation.
At Chase Lodge Hospital, we have the highest-skilled professionals who will read your results sensitively and accurately. If you have an abnormal liver function test or are worried about your liver health, see your GP or make time to chat with us. Early action can save lives and improve long-term outcomes.