<qa>  What is NAFLD defined by?Non-alcoholic fatty liver disease NAFLD is defined by presence of hepatic steatosis fat accumulation in liver cells, either by imaging or by biopsy and absence of causes for secondary hepatic fat accumulation such as significant alcohol consumption, medications, or hereditary disorders. In the majority of patients, NAFLD is associated with risk factors for cardiovascular disease such as obesity, diabetes mellitus, and high cholesterol, and may lead to irreversible liver damage. Non-alcoholic steatohepatitis NASH is a more severe form of NAFLD and is present in up to 30 of obese adults. NASH is defined by hepatic steatosis and inflammation with hepatocyte injury with or without fibrosis hardening of the liver. 