What are MASLD and MASH?

Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD) is a type of steatosis (fat) in the liver caused by factors other than alcohol use. Often, MASLD occurs in conjunction with other metabolic disorders such as high cholesterol, obesity, and diabetes. MASLD is often unrecognized and underdiagnosed due to a lack of symptoms. Persons with obesity and diabetes should be evaluated for fatty liver disease.

Metabolic Dysfunction-Associated Steatohepatitis (MASH) is a more severe form of MASLD, where fibrosis (scarring) of the liver tissue occurs. It is a serious condition that can progress to cirrhosis and potentially result in the need for liver transplantation or death. Among the five per cent of Canadians with MASH, approximately 17 per cent are predicted to have advanced disease. 

Note: MASLD and MASH were formerly named NAFLD and NASH, respectively, until 2023, when a large group study renamed these diseases.

Due to the co-epidemic of obesity and type 2 diabetes, MASLD is the most common liver disease in our country, affecting one in five Canadians. 

MASH is the second leading indication to liver transplant in Canada, and is projected to become the main one within 10 years.

"Unfortunately, the combination of obesity and diabetes within an aging population has created a 'perfect storm' for the progression of fatty liver disease," observes Jennifer Nebesky, President and CEO of the Canadian Liver Foundation (CLF). "This is compounded by the fact that there is very little awareness about fatty liver among the general Canadian population. Without this knowledge, individuals cannot work with their physicians to proactively detect and treat their illness."