[Metabolic fatty liver diseases: hepatic consequences of the metabolic syndrome].

Metabolic fatty liver diseases (Non Alcoholic Fatty Liver Diseases-NAFLD) are liver abnormalities (steatosis and steatohépatitis) commonly related to visceral obesity and to the metabolic syndrome. The pathogenesis of metabolic fatty liver diseases is most probably linked to the adipose tissue insulin resistance with a very high free fatty acids release, an abnormal secretion of factors produced by the adipose tissue (adipokines) and a low grade of chronic inflammation. The link between metabolic fatty liver diseases and the metabolic syndrome is further supported by epidemiological studies, as well as the frequently encountered cardio-vascular complications in both diseases. Changes in lifestyle with dietary restriction and increased physical activity are mandatory and similar for both conditions. Drugs such as thiazolidinediones, known to reduce insulin resistance and inflammation, still need further evaluation.