Question: What are the symptoms of NAFLD in children?
Answer: Usually, nonalcoholic fatty liver disease, or NAFLD (also referred to as metabolic dysfunction-associated steatotic liver disease, or MASLD), is a silent disease with few or no symptoms. Children may not have symptoms even if they develop cirrhosis due to nonalcoholic steatohepatitis, or NASH (also referred to as metabolic dysfunction-associated steatohepatitis, or MASH).

Once symptoms arise, however, a child may already have permanent liver damage. If children do have symptoms from NASH, they may feel tired, become tired easily, or have discomfort over the liver, in the upper right side of the abdomen.
Question: What causes NAFLD in children?
Answer: Experts are still studying the causes of NAFLD. Research suggests that certain health problems, genes, and other factors may make some children more likely to develop NAFLD.

Health problems

Children with the following health problems are more likely to develop NAFLD

overweightorobesity.
insulin resistanceortype 2 diabetes.
highblood pressure.
abnormal levels offatsin the blood, which may includehigh levels oftriglycerides.abnormal levels ofcholesterol—typically high total cholesterol, highLDL cholesterol, or lowHDL cholesterol.
high levels oftriglycerides.
abnormal levels ofcholesterol—typically high total cholesterol, highLDL cholesterol, or lowHDL cholesterol.
metabolic syndrome, or one or more traits of metabolic syndrome. Metabolic syndrome is a group of traits and medical conditions linked to overweight and obesity. Doctors typically define metabolic syndrome in children as a combination of three or more of the following featureslarge waist size.high levels of triglycerides in the blood.low levels of HDL cholesterol in the blood.high blood pressure.higher-than-normalblood glucoselevels or a diagnosis of type 2 diabetes.
large waist size.
high levels of triglycerides in the blood.
low levels of HDL cholesterol in the blood.
high blood pressure.
higher-than-normalblood glucoselevels or a diagnosis of type 2 diabetes.

Doctors may not be able to diagnose metabolic syndrome in children younger than age 10. Children in this age group may still have traits of metabolic syndrome.

Experts do not know for sure why some children with NAFLD have nonalcoholic fatty liver, or NAFL (also referred to as metabolic dysfunction-associated steatotic liver, or MASL), while others have NASH. Research suggests that NASH is more common in children who have both NAFLD and type 2 diabetes.3

Genes

Certain genes may increase a child’s chance of developing NAFLD. These genes may explain why NAFLD is more common in Hispanic and Asian American children than in Black children. Genes may also explain why NAFLD sometimes runs in families.

Experts are still studying the genes that may play a role in NAFLD.

Other factors

Scientists are studying other factors that may play a role in causing or worsening NAFLD in children. These include

birthweight. Research suggests that children who had a high or low birthweight are more likely to develop NAFLD.
changes in the microbiome—thebacteriain thedigestive tractthat help withdigestion. Studies have found differences between the microbiomes of children who have NAFLD and those who do not.
diets high in fructose—asugarthat is part of table sugar and is also commonly added to sweeten drinks and foods. Studies suggest that diets high in fructose may increase the risk of NAFLD.
Question: Is NAFLD the only cause of fatty liver in children?
Answer: Fatty liver may have causes other than NAFLD. If medical tests suggest that a child has a buildup of fat in the liver, the doctor may ask questions and order tests for other causes.

Other causes of fatty liver in children include

disorders, called lipodystrophies, that cause a child’s body to use or store fat improperly
celiac disease
rapid weight loss ormalnutrition
some medicines, including those used to treatmental disorders,nervous system disorders, orskin conditions
exposure to some toxins
rare genetic diseases, such asWilson diseaseandhypobetalipoproteinemia
alcohol-associated liver disease—damage to the liver and its function due to excessivealcohol consumption