Non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) describes several conditions due to a build-up of fat in the liver. It can affect anyone. It’s most common in overweight adults, over 40, with related conditions (see below). There’s currently no cure but if diagnosed early it can be managed with lifestyle changes.


A healthy liver should contain little or no fat. Early-stage NAFLD doesn't usually cause any harm, but it can lead to serious liver damage, including cirrhosis, if it gets worse.

Having high levels of fat in your liver is also associated with an increased risk of problems such as:

There’s currently no cure but if detected and managed at an early stage, it's possible to stop NAFLD getting worse and reduce the amount of fat in your liver.

Stages of NAFLD

NAFLD develops in four main stages. Most people will only ever develop the first stage, usually without realising it. In a small number of cases, it can progress and eventually lead to liver damage if undetected and managed.

The main stages are:

  • simple fatty liver (steatosis) – a largely harmless build-up of fat in the liver cells that may only be diagnosed during tests carried out for another reason
  • non-alcoholic steatohepatitis (NASH) – a more serious form of NAFLD, where the liver has become inflamed
  • fibrosis – where persistent inflammation causes scar tissue around the liver and nearby blood vessels, but the liver is still able to function normally
  • cirrhosis – the most severe stage, occurring after years of inflammation, where the liver shrinks and becomes scarred and lumpy; this damage is permanent and can lead to liver failure and liver cancer

It can take years for fibrosis or cirrhosis to develop. It's important to make lifestyle changes to prevent the disease getting worse.

People at an increased risk of NAFLD

You're at an increased risk of NAFLD if you:

  • are obese or overweight – particularly if you have a lot of fat around your waist

NAFLD has been diagnosed in people without any of these risk factors, including young children.

Although it's very similar to alcohol-related liver disease (ARLD), NAFLD isn't caused by drinking too much alcohol.

Symptoms of NAFLD

There aren't usually any symptoms of NAFLD in the early stages. You probably won't know you have it unless it's diagnosed during tests carried out for another reason.

Occasionally, people with NASH or fibrosis may experience:

  • a dull or aching pain in the top right of the tummy (over the lower right side of the ribs)
  • fatigue (extreme tiredness)
  • unexplained weight loss
  • weakness

If cirrhosis (the most advanced stage) develops, you can get more severe symptoms such as:

Diagnosis of NAFLD

NAFLD is often diagnosed after a blood test called a liver function test produces an abnormal result and other liver conditions, such as hepatitis, are ruled out.

The condition may also be spotted during an ultrasound scan of your tummy.

If you're diagnosed with NAFLD, further tests may be needed to fid out which stage you have. This may involve a special blood test or having another type of ultrasound scan.

Some people may also need a small sample of liver tissue (biopsy) taken to have it analysed.

Treatment for NAFLD

Most people with NAFLD won't develop any serious problems. If you're diagnosed with the condition it's a good idea to take steps to stop it getting any worse.

There's currently no specific medication for NAFLD, but making healthy lifestyle choices can help. Treatment may be recommended for associated conditions or complications.

You may be advised to have regular appointments with your doctor to:

  • check your liver function
  • look for signs of new problems

Healthy diet and lifestyle

Adopting a healthy lifestyle is the main way of managing NAFLD. The following can all help:

NAFLD isn't caused by alcohol, but drinking may make the condition worse. It's advisable to cut down or stop drinking alcohol.


There isn't currently any medication to treat NAFLD, but various medicines can be useful in managing the problems associated with the condition. Your GP will be able to discuss medication options with you.

Liver transplant

If your liver stops working properly, you may need a liver transplant. For adults, the average waiting time for a liver transplant is around four to five months for transplants from recently deceased donors. It may be possible to have a transplant using a section of liver removed from a living donor.

The information on this page has been adapted from original content from the NHS website.

For further information see terms and conditions.

This page was published May 2018

This page is due for review May 2019

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