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(NAFLD, Nonalcoholic Steatohepatitis [NASH])


Nonalcoholic fatty liver disease (NAFLD) is a buildup of fat in the liver that is not caused by drinking alcohol.

The Liver
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NAFLD happens when the liver cannot break down fats and they build up in liver tissue. Many health problems can make it hard for the liver to break down fats.

Risk Factors

Things that may raise the risk of NAFLD are:

  • Obesity
  • Diabetes
  • Metabolic syndrome
  • High triglyceride levels
  • A large waistline
  • Severe weight loss
  • Some medicines
  • Exposure to certain chemicals


Most people do not have symptoms. Those who do may have:

  • Fatigue
  • Pain in the upper right side of the belly
  • Muscle weakness
  • Yellowing of the skin and the white part of the eyes


The doctor will ask about your symptoms and health history. A physical exam will be done.

Blood tests will be done to look for raised liver enzymes.

Images may be taken to look at the liver. This can be done with:

A sample of the liver may be tested. This can be done with a liver biopsy .


The cause of NAFLD will need to be treated. Options may be:

  • Working with a dietitian to eat a healthful diet to lose weight
  • Exercising regularly
  • Medicine to treat the cause of NAFLD

People with severe symptoms may need bariatric surgery.


The risk of NAFLD can be lowered with diet and exercise.


American Liver Foundation  https://www.liverfoundation.org 

National Institute of Diabetes and Digestive and Kidney Diseases  https://www.niddk.nih.gov 


Canadian Liver Foundation  https://www.liver.ca 

Health Canada  https://www.canada.ca 


Nonalcoholic fatty liver disease. American Liver Foundation website. Available at: https://www.liverfoundation.org/for-patients/about-the-liver/diseases-of-the-liver/non-alcoholic-fatty-liver-disease. Accessed May 5, 2020.

Nonalcoholic fatty liver disease (NAFLD). EBSCO DynaMed website. Available at:  https://www.dynamed.com/condition/nonalcoholic-fatty-liver-disease-nafld  . Updated December 17, 2019. Accessed May 5, 2020.

Nonalcoholic steatohepatitis. National Institute of Diabetes and Digestive and Kidney Diseases website. Available at: https://www.niddk.nih.gov/health-information/liver-disease/nafld-nash. Accessed May 5, 2020.

Rinella ME. Nonalcoholic fatty liver disease: a systematic review. JAMA. 2015 Jun 9;313(22):2263-2273.

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