Nonalcoholic fatty liver disease (NAFLD) prevention: role of Mediterranean diet and physical activity

摘要

Nonalcoholic fatty liver disease(NAFLD)is one of the most common causes of chronic liver disease in Western countries leading to high morbidity and mortality and is strongly related to obesity(1).Indeed,metabolic syndrome and insulin resistance play a role in the pathogenesis of NAFLD,which involves intrahepatic triglyceride accumulation and inflammation(2).NAFLD is a consequence of genetic predisposition interacting with environmental and behavioral factors.Data within the literature strongly support the idea that it represents the hepatic feature of a multisystem disease together with type 2 diabetes,cardiovascular disease(CVD),chronic kidney disease and osteoporosis(3).Nevertheless,the exact mechanism of hepatic fat accumulation and the progression to nonalcoholic steatohepatitis(NASH)is not completely understood.Hepatic fat is closely related to cardiometabolic risk(4)and,in order to decrease intrahepatic lipid(IHL)content and improve NAFLD,lifestyle interventions involving both diet and physical activity are recommended(2).In particular,great attention is focused on Mediterranean diet,which seems to help in gradually improving the severity of NAFLD(5).A randomized,cross-over intervention study demonstrated that in just 6 weeks,an olive-oil rich Mediterranean diet can result in a 40%relative reduction in liver fat measured by magnetic resonance in the form of IHL%(6).NAFLD improvement was associated with increased insulin sensitivity and reduced circulating insulin concentrations,even without a change in body weight(6).