Liver disease caused by too much fat being deposited in the liver is the most common form of liver disease in the world. People tend to think of liver disease, and especially cirrhosis, as a problem caused by alcohol, but that is not always the case. Liver disease caused by fat buildup is usually a silent condition for many years, meaning that people with this condition have very few if any symptoms until significant damage has been done. Let’s talk about what you should know.
What’s in a name?
This condition has just been renamed, so I wanted to let you know the different names that you might see if you are trying to read more about it. The old name was nonalcoholic fatty liver disease (NAFLD), which included 2 conditions; nonalcoholic fatty liver (NAFL) and nonalcoholic steatohepatitis (NASH). These names have been used for many years but were changed in June 2023. The new names are metabolic dysfunction associated steatotic liver disease (MASLD) and metabolic dysfunction associated steatohepatitis (MASH). There were several reasons for the name change but one big reason was to more clearly indicate the underlying problem (metabolic dysfunction), rather than indicating what was NOT the cause (alcohol). I will be using the new terminology but many articles that you will see online will still have the old terminology. Just remember that they are the same disease, just with a new name.What is MASLD and MASH, and how do they differ?
MASLD is a condition in which too much fat is deposited in the liver. It can be seen on imaging studies, such as ultrasounds and CT scans. But it is not causing problems with liver function yet. MASLD can be present for many years with no symptoms. MASLD can progress to MASH.
MASH starts when the buildup of fat starts to cause inflammation in the liver (hepatitis). MASH causes liver swelling and damage to the cells in the liver. This can lead to scarring, fibrosis, and eventually to cirrhosis. It can lead to liver cancer and is a leading cause of liver transplantation.
What does metabolic dysfunction mean?
Essentially this means that the usual way that the body makes and uses energy is disrupted.
What causes metabolic dysfunction?
There are many things that can cause metabolic dysfunction. They include:
-
Genetic conditions
-
Unhealthy diet
-
Sedentary lifestyle
-
Low thyroid function
What are the symptoms of MASLD and MASH?
MASLD often causes no symptoms. If symptoms occur, they are usually vague, such as:
-
Fatigue
-
Feeling unwell without a specific idea of why
-
Discomfort in the right upper part of the abdomen.
Symptoms of NASH can include:
-
Persistent itching
-
Abdominal swelling due to fluid buildup in the abdomen
-
Shortness of breath
-
Leg swelling
-
Redness of the palms
-
Small, spider-like vessels just beneath the surface of the skin
-
Jaundice – Yellow appearance of the skin and eyes
What are the factors that increase your risk for MASLD and MASH?
Risk factors for MASLD include:
-
High cholesterol and/or high triglyceride levels
-
Obesity, especially when fat is centered in the waist
-
Insulin resistance or Type 2 diabetes
-
Metabolic syndrome
-
Polycystic ovarian syndrome
-
Obstructive sleep apnea
-
Family history of liver disease or obesity
-
Hormone issues such as:
-
Underactive thyroid
-
Underactive pituitary gland
-
Growth hormone deficiency
-
MASLD is more likely to progress to MASH in people who:
-
Are over 50 years of age
-
Have certain genetic risk factors
-
Are obese
-
Have diabetes or high blood sugar
-
Have symptoms of metabolic syndrome (high blood pressure, high triglycerides, large waist size)
Next week, we will talk more about the complications of MASLD and NASH, along with how it is diagnosed and treated, and what you might do to prevent it.
This link will take you to a video done by the American Liver Foundation that I thought was very informative.
If you have any questions about fatty liver disease, please log into your account and send us your question. We are here to help.
Dr. Anita Bennett MD – Health Tip Content Editor