Some individuals develop fatty liver disease. It is now well established that hepatic steatosis is frequently associated with obesity, insulin resistance and type 2 diabetes mellitus, or with excessive alcohol intake. Although clearly different in their metabolic origins, it is recognised that nonalcoholic and alcoholic fatty liver disease share several features and, most importantly, that accumulation of fat in the liver is not
a benign condition. Excess fat increases the vulnerability of hepatocytes to potential harmful effects of metabolic stress imposed by cytokines, viral infections and oxidative agents. As a consequence, hepatic steatosis is a factor predisposing to development of fibrosis and cirrhosis. This article reviews pathophysiology, diagnostic and therapeutic methods according to the currently recommended standards.