MASLD (previously called Nonalcoholic Fatty Liver Disease, or NAFLD) occurs when an excessive amount of fat accumulates in the liver of people who consume minimal to no alcohol. MASLD is very common, affecting as many as 100 million people in the U.S. It’s now the leading cause of chronic liver disease worldwide.
All livers contain some fat. Normal fat levels in the liver are between 5 and 10 percent. If your liver has more fat than that, you may have MASLD. Fatty liver disease can also be caused by alcohol consumption over time, which is called alcoholic fatty liver disease (now known as MetALD). While these conditions have different causes, you can have both MASLD and AFLD at the same time.
About 25% of people with MASLD will get nonalcoholic steatohepatitis (NASH), also referred to as metabolic dysfunction-associated steatohepatitis (MASH), which damages the liver. MASLD increases your risk of developing heart disease, liver cancer and cirrhosis (permanent scarring of the liver).