What is the liver and what does it do?

• It helps process the food we eat.
• It removes waste and toxic substances from the blood.
• It helps make proteins and hormones that the body needs to function.

What is metabolic dysfunction-associated steatotic liver disease (MASLD)?

Metabolic dysfunction-associated steatotic liver disease (MASLD) or simply “steatotic liver disease” is a problem caused when too much fat remains in the liver. Extra fat in the liver can occur in children and adults. It can also happen in adults and young people who drink alcohol.

MASLD can be mild to severe.

MASH: Some people with steatotic liver have a more severe form that includes damage (inflammation) inside the liver. This is called metabolic dysfunction-associated steatohepatitis, or MASH.

Cirrhosis: Over time, MASH can cause scar tissue to develop in the liver. Eventually, the scar tissue replaces healthy liver cells and the liver cannot function. This is called cirrhosis.

Why was there a change in the name of this liver disease?

MASLD was formerly known as fatty liver disease or non-alcoholic fatty liver disease (NAFLD). It is most common chronic liver diseases around the world, affecting more than 30% of the world’s population. The worldwide liver community agreed that there was a need for better terms for this liver disease that did not embarrass people and that clearly distinguished this condition from alcohol consumption.

What causes a steatotic liver?

A steatotic liver is a very common disorder that affects about one in ten children in the United States. The most common reason for the build-up of steatosis in the liver is too much weight gain.

About half of overweight and obese children may have a steatotic liver. Children who gain more abdominal fat may be at greater risk of a steatotic liver. Other risk factors for a steatotic liver are having a family member with a steatotic liver, type 2 diabetes, insulin resistance, or polycystic ovary syndrome.

How is steatotic liver disease diagnosed?

A steatotic liver is usually suspected in children who are obese with a body mass index (BMI) >85%.

If your pediatrician suspects a steatotic liver, they will order a blood test to check your child’s liver function. In a child with steatotic liver, a blood test will often show elevated levels of a protein called ALT (alanine aminotransferase). This result suggests that there is liver inflammation. Sometimes a pediatrician will also perform an abdominal ultrasound, which can show if there is too much steatosis in the liver.

Other conditions such as viral hepatitis, autoimmune hepatitis and metabolic diseases can also cause steatosis accumulation in the liver. Your doctor will take appropriate blood tests to make sure your child does not have other liver diseases.

Once a diagnosis of a steatotic liver is confirmed, other tests can be used to gauge how severe it is. An MRI (magnetic resonance imaging) scan can measure how much steatosis is in the liver and can look for scar tissue (fibrosis). A liver biopsy in some cases can also be useful to measure inflammation and scar tissue.

How is a steatotic liver treated?

The first treatment for a steatotic liver is to try to change the diet by reducing added sugar. This includes limiting things like sugar-sweetened beverages, sugary foods, and all juices. The American Heart Association recommends 25 grams or less a day of added sugar for children, and children with fatty liver may need even less.

In addition to changing the diet, increased exercise can promote weight loss and reduce a steatotic liver. Increasing daily physical activity such as playing sports, going to a playground, walking and other activities can be helpful. Current recommendations suggest 30-60 minutes of activity per day, and children with steatotic liver may need even more.

Because a steatotic liver does not always improve with better diet and exercise, children with a steatotic liver are sometimes treated with medication. At present, there are no approved medications for a steatotic liver. Research studies are currently testing medications to help with a steatotic liver, especially when there is inflammation and scar tissue. Ask your doctor about research studies in your area or visit Clinicaltrials.gov.

Authors: Abha Kaistha, MD, Vania Kasper, MD, and Miriam Vos, MD, February 2020.
Updated March 2024: Author Jay Hochman, MD
Editor: Christine Waasdorp, March 2024