Non-Alcoholic Fatty Liver Disease (NAFLD)

*Also known as Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD)

NAFLD has increased in both adults and children in recent years and is now one of the most common forms of chronic liver disease in children and adolescents.

*This website provides general information but does not replace medical advice. It is important to contact your/your child’s medical team if you have any worries or concerns

NAFLD and MASLD terminology

In June 2023, a group of multi-national liver societies announced that non-alcoholic fatty liver disease (NAFLD) will now be known as metabolic dysfunction-associated steatotic liver disease (MASLD).

In addition to this, non-alcoholic steatohepatitis (NASH) will be known as metabolic dysfunction-associated steatohepatitis (MASH).

These change have taken place in an effort to introduce terminology that is clearer, reflects the causes of the conditions and moves away from stigmatizing language such as “fatty” and “alcoholic”.

You may see both sets of terms being used for the next few years and CLDF online and printed literature currently uses the older terminology.

View our blog post for more information.

What is non-alcoholic fatty liver disease (NAFLD)?

NAFLD has increased in both adults and children in recent years and is now one of the most common forms of chronic liver disease in children and adolescents.

NAFLD occurs when you have too much fat in your liver. The liver is a very active organ, taking food directly from the gut and processing fat, carbohydrates and protein into energy and other proteins. In some people there is an imbalance in this process. This may be a result of too much fat coming into the liver cell, overwhelming the machinery that processes it or a subtle change in the cells’ ability to process (metabolise) or transport the fats/carbohydrates.

In some people, the liver cells simply accumulate fat droplets that do not irritate their liver. However, in others, the fat droplets act like splinters and cause an inflammatory response leading to the formation of scars.

NAFLD refers to a group of conditions which can be understood in terms of different stages:

  1. Simple steatosis – this is fat building up in the liver.
  2. Non-alcoholic steatohepatitis (NASH) – inflammation (swelling in the liver) caused by build-up of fat
  3. NASH with fibrosis – scarring in the liver, which causes damage
  4. Cirrhosis – usually the result of long-term, continuous damage to the liver. Irregular bumps, known as nodules, replace the smooth liver tissue which makes the liver harder. Cirrhosis can progress to end stage liver disease. This is when the liver doesn’t work properly and is stiff, leading to a build up of pressure (portal hypertension).

What is non-alcoholic steatohepatitis (NASH)?

NASH occurs when there is inflammation of the liver associated with a build-up of fat. This inflammation is often associated with scarring. Most scarring, up to the point of early cirrhosis, is reversible. However, a small proportion of children with NASH may go on to develop cirrhosis and further complications. The exact cause of progression from simple steatosis to NASH and cirrhosis is unknown.As liver scarring (or fibrosis) advances, the spleen may appear enlarged on an ultrasound scan. This happens because the liver is stiff as a result of scarring, leading to blood flow being affected by back pressure. As the spleen and the liver are connected, this pressure is transmitted to the spleen via the splenic vein, causing the spleen to increase in size due to its elasticity.See CLDF’s leaflet Portal Hypertension and Ascites for more information.

Why do children get NAFLD?

Clinical research into why children develop NAFLD is increasing.

We know that there are multiple reasons for NAFLD which are environmental and genetic. Children and young people may be at high risk of developing this condition if they:

  • are overweight or obese
  • have insulin resistance
  • have type 2 diabetes
  • follow a poor diet and do little or no exercise
  • have dyslipidaemia – irregular level of blood lipids
  • carry certain variations in their genes

Other conditions can look like NAFLD and need to be ruled out through investigations because their treatments are very different. These conditions may include:

  • malnutrition
  • certain types of metabolic liver disease such as Wilson’s disease, fructosaemia and cystic fibrosis
  • artificial feeding such as feeding directly into a vein (parenteral feeding)

Taking certain drugs prescribed for other conditions may also lead to features similar to NAFLD.

What are the signs?

Many children who have NAFLD do not display symptoms in the early stages. It is often once significant damage to the liver has occurred that signs become more obvious.

Some children may report symptoms such as:

  • abdominal pain
  • fatigue
  • irritability
  • headaches
  • difficulty concentrating
  • low mood and anxiety
  • changes to skin colour where two areas of skin touch and/or joints

If cirrhosis (the most advanced stage) develops, the following symptoms may be present:

  • yellowing of the skin and the whites of the eyes (jaundice)
  • itchy skin (pruritus)
  • swelling of the lower tummy (ascites)
  • bruising easily
  • dark urine

How is NAFLD diagnosed?

Liver disease can have very few symptoms therefore an honest discussion with your child’s doctor about their health and lifestyle will increase the chance of them being able to provide an accurate diagnosis.

There is no specific test for NAFLD and most children are diagnosed because they are having tests for something else e.g. routine blood tests and ultrasound scans.

Blood tests may show raised liver enzyme levels which will lead to further investigations. An ultrasound scan and further blood tests will be done to rule out other liver conditions. In some children, a liver biopsy may be needed to confirm the diagnosis and assess the liver.

Download the NAFLD leaflet above to see the full range of tests that may be undertaken.

What happens if my child/teenager is diagnosed with NAFLD?

If diagnosed in the early stages, it is possible to stop NAFLD progressing to the point of liver damage.

Children and young people with NAFLD need medical follow up to detect changes in their condition as early as possible.

We know that in most cases, lifestyle change with a major focus on healthy eating and increasing activity can reverse the condition completely even when significant scarring is present. In adult studies, weight loss of 10% of the total body weight has led to reversal of this condition.

Specific advice and treatment may be given to children if NAFLD has progressed to a later stage or are known to have complications of cirrhosis.

Can NAFLD be prevented?

It is not always possible to avoid NAFLD because factors such as genetics and other unknown causes cannot be prevented. Reducing risk through exercise, healthy eating and better control of existing medical conditions can help prevent the development and progression of NAFLD.

It is important to remember that NAFLD does not develop just because a child has eaten too much or is overweight or obese. The distribution of fat is more important than total weight. Children who have a normal weight but carry fat around their middle can develop NAFLD. For these children, attention to being fit and healthy is key.

How is NAFLD treated?

There is currently no agreement on appropriate medications to treat NAFLD. Research and clinical trials in this area are being explored and can be discussed with your child’s medical team. We know that the amount of fat in the liver can be reduced through weight loss, eating healthily and regular exercise.

One of the key people you should see is a dietitian who can advise you and your child on how to make achievable healthy lifestyle choices that are specific to your child.

Diet and lifestyle changes

As a parent, there’s lots you can do to help your child become a healthier weight. Getting them to be more active and eat well is important. This isn’t an easy option and it requires commitment from the whole family to change your lifestyle.


  • Follow a healthy portion-controlled diet and avoid adult-sized portions for children and young people.
  • For younger children, serve their meals on a child sized plate. This makes it easier to give your child the correct portion size and will seem more satisfying.
  • Lots of foods have hidden fat, sugar and salt. Make sure you check the labels on food and know what the food you are eating contains.
  • Swap sugary drinks for water or zero sugar/low calorie drinks.
  • Swap sugar-coated breakfast cereals for wholegrain or brown cereals e.g. porridge, wholegrain cereal with no added sugar. Alternatively, mix cereals such as rice cereals with wheat-based biscuits.
  • Include beans and lentils in your diet to increase fibre intake. Replacing some meat in a casserole with these options will reduce the fat content too.
  • Try to grill, bake or poach food rather than frying.
  • Aim for five portions of fruit and vegetables a day.

Activity and Lifestyle:

  • Avoid eating in front of the TV because you can eat more without noticing. Encourage family meals, switch off the TV and remove other distractions during mealtimes.
  • Sleep is important – ensure enough sleep with a prompt bedtime. Limiting screen time and doing more physical activities will help too.
  • Children and young people should have at least 60 minutes of physical activity a day. Make use of school clubs, local parks, riding bikes, try out a new sport and walk wherever possible.
  • Alcohol and smoking can be dangerous for teenagers and young people with liver problems. Speak to a member of your medical care team about safe limits.

If your child doesn’t have a dietitian and you would like more support around diet and lifestyle speak to your medical team or GP. They will know about local weight management and activity programmes, useful resources and can make a referral to a dietitian.

Liver transplant

If the liver becomes damaged so much that it can’t work properly a transplant may be required. This is very rare in children and is usually only recommended if other treatments or lifestyle changes are no longer helpful. For more information about liver transplants see the CLDF leaflet “Liver Transplantation”.

Complementary and alternative medicines

There are many websites offering dietary advice through complementary or alternative medicines. If your child is diagnosed with a liver condition it is important to seek advice from their doctor and dietitian because these professionals are regulated to provide health advice specific to your child.

Where can I get support from?

There are lots of different places you can access support in addition to your medical team.

CLDF has a Families Team offering non-judgmental support who can help you after a diagnosis. If you require further information, need someone to talk to or would like to meet others in a similar situation then the Families Team can help you. You can call 0121 212 6023 or email

CLDF also have a Young People’s Digital and Engagement Officer who can provide support specifically to those aged 11 – 24. You can call 0121 212 6024 or email

There are lots of resources available with ideas for being healthier, easy recipes and meal ideas as well as ideas for getting active. Here are just a few:

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