Non-alcoholic fatty liver disease

Metabolic (dysfunction) associated fatty liver disease (MAFLD) was previously known as non-alcoholic fatty liver disease (NAFLD) until renamed in 2023 by a global consensus panel composed mostly of hepatology researchers and clinicians. The term metabolic dysfunction-associated steatotic liver disease (MASLD) is also used. MAFLD is excessive fat build-up in the liver without another clear cause such as alcohol use. There are two types; non-alcoholic fatty liver (NAFL) and metabolic dysfunction–associated steatohepatitis (MASH; formerly non-alcoholic steatohepatitis, NASH), with the latter also including liver inflammation. Non-alcoholic fatty liver is less dangerous than NASH and usually does not progress to NASH. When NAFL does progress to NASH, it may eventually lead to complications such as cirrhosis, liver cancer, liver failure, or cardiovascular disease. The umbrella term steatotic liver disease (SLD) covers MASLD and MetALD, a term describing people with MASLD who consume more than 140 grams of alcohol per week for women and 210 grams per week for men. Obesity and type 2 diabetes are strong risk factors for MAFLD. Other risks include being overweight, metabolic syndrome (defined as at least three of the five following medical conditions: abdominal obesity, high blood pressure, high blood sugar, high serum triglycerides, and low serum HDL cholesterol), a diet high in fructose, and older age. MAFLD and alcoholic liver disease are types of fatty liver disease. Obtaining a sample of the liver after excluding other potential causes of fatty liver can confirm the diagnosis. Treatment for MAFLD is weight loss by dietary changes and exercise. There is tentative evidence for pioglitazone and vitamin E; and bariatric surgery can improve or resolve severe cases. Those with NASH have a 2.6% increased risk of dying per year. MAFLD is the most common liver disorder worldwide and is present in approximately 25% of the world's population. It is very common in developed nations, such as the United States, and affected about 75 to 100 million Americans in 2017.