How to test your liver function at home

What is a liver function blood test?

A liver blood test was formerly known as a liver function test or LFT. The name has changed to reflect new guidance from the British Liver Trust published in 2022.

When analysed on its own, a liver blood test can’t diagnose or rule out liver disease. This means your liver blood test results might be normal even if you have liver disease.

What does the liver do?

The liver is an organ that sits in the upper part of your stomach and is essential for your health. It plays a role in over 500 functions in your body. These include:

• creating bile acids that help you digest food
• breaking down and storing nutrients
• detoxifying your blood
• fighting infections
• helping your blood to clot
• maintaining hormone balances
• regulating blood sugar levels

What's included in a liver function test?

A liver function test measures proteins, enzymes, and waste products in your blood to assess liver health.

The test evaluates liver health through three categories of markers:

• Liver proteins: These include albumin, globulin, and total protein.
• Liver enzymes: These include ALT, ALP, and GGT.
• Bilirubin: These reflect the liver's capacity to process waste products.

What can a liver blood test tell you?

A liver blood test measures the levels of various things in your blood, like proteins, liver enzymes, and bilirubin. This can help check the health of your liver and the signs of inflammation or damage.

Your liver can be affected by:

• liver infections like hepatitis B and hepatitis C
• non-alcoholic fatty liver disease
• alcohol-related liver disease
• scarring on your liver (cirrhosis)
• gallbladder disease
• possible side effects of medications and herbal remedies — like St John’s Wort
• haemochromatosis — when your body stores too much iron
• autoimmune conditions — when your body reacts and attacks itself

Who should do a liver blood test?

A liver function test can be useful for people who have risk factors for liver disease. Some reasons you may want to check your liver function include:

• have symptoms of fatigue and nausea
• drink more than 14 units of alcohol a week
• are worried about fatty liver disease
• are overweight
• have type 2 diabetes
• have raised cholesterol
• have a genetic disease — like haemochromatosis
• are taking medications which affect your liver

How does a home liver function blood test work?

You can check your liver health by using a liver blood test at home.

Home blood testing providers like Thriva offer test kits that let you collect your sample when it's convenient for you. A doctor will review your results alongside information about your overall health, such as your diet, alcohol consumption, weight, and previous test results.

If your results show that you may have an underlying health condition, they'll refer you for further testing. You can also arrange a digital appointment to speak about your results.

Learn more about how home blood tests work.

What if your liver blood test results contain abnormalities?

If your liver blood test results are abnormal, we recommend following them up with a healthcare professional. They will investigate your results further to help rule out or diagnose liver disease. 

Mild to moderate abnormalities in liver blood test results are commonly associated with: 

• non-alcoholic fatty liver disease
• alcohol-related liver disease — for example, you might have elevated gamma-glutamyl transpeptidase (GGT) levels
• certain medication — like some antibiotics, anti-epileptic drugs, and non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen
• infections like hepatitis B and C

What affects your liver health?

Drinking too much alcohol can affect your liver, and over time, it can lead to alcohol-related fatty liver disease. Research suggests this might result from waste products in alcohol that cause your liver to make more fatty acids.

Over time, consistent inflammation can cause permanent scarring on the liver, called cirrhosis. This can lead to liver failure.

Being overweight or obese can also impact your liver, potentially leading to non-alcoholic fatty liver disease. Your risk might be higher if you also have:

• high cholesterol or triglycerides
• high blood pressure
• type 2 diabetes
• smoking
• lack of exercise

Finally, certain medications like steroids and non-steroidal anti-inflammatories (e.g. ibuprofen) can impact your liver if you take them for a long time.

How to improve your liver health

Lifestyle changes can make a big difference in your liver health, particularly if liver disease is caught early. However, you should always follow the advice of your doctor.

Some lifestyle factors that can positively impact your liver health include:

• Limiting the amount of alcohol you have a week to 14 units, which is equivalent to 6 pints of beer or 6 medium glasses of wine.
• Losing weight if you’re overweight or obese.
• Following a healthy, balanced diet that is rich in fruits, vegetables, whole grains, and healthy fats.
• Ensuring you get enough exercise by including movement you enjoy.

Takeaway

Liver blood tests can't diagnose liver disease on their own, but they're useful early-warning tools. Home tests provide convenient monitoring, helping you understand your risk factors.