Condition Basics
What is metabolic dysfunction-associated steatotic liver disease (MASLD)?
Metabolic dysfunction-associated steatotic liver disease (MASLD) is the term for conditions in which fat builds up in the liver due to metabolic stress from high blood sugar, high cholesterol, high blood pressure, or extra body weight. It used to be called nonalcoholic fatty liver disease (NAFLD).
What causes it?
Experts don't know why some people get a buildup of fat in their liver and some don't. They do know that MASLD is often linked to a group of health conditions called metabolic syndrome, which includes:
- Obesity.
- Insulin resistance or type 2 diabetes.
- High cholesterol and high triglycerides.
- High blood pressure.
Most people who have MASLD also have one or more of these health problems. But MASLD can occur in people who have none of these conditions.
What are the symptoms?
Most people who have MASLD have no symptoms. Even people who have the more serious type called MASH may not have symptoms for many years. When symptoms occur, they may include feeling very tired. Or you may have pain or discomfort in the upper right part of your belly.
How is it diagnosed?
Your doctor will ask about your past health and any symptoms and will do a physical exam. The doctor may also do tests. For example, you may have:
- Blood tests, such as liver function tests.
- Imaging tests, such as an abdominal ultrasound, a CT scan, or an MRI.
Testing can help the doctor rule out other possible causes of fat in the liver. These include heavy alcohol use, certain medicines, and other liver diseases.
A special type of ultrasound or MRI may be done to see if a liver biopsy is needed. In a liver biopsy, a sample of liver tissue is removed and sent to a lab. A liver biopsy can show if you have scarring or the more serious type of MASLD called MASH.
How is MASLD treated?
Treatment focuses on managing related conditions like diabetes and making lifestyle changes, including losing weight if needed, eating a healthy diet, and being more active. A doctor may prescribe medicines for related conditions or to help with weight loss. Weight-loss surgery may be an option for people who have obesity.