The effect of diet on the presence and management of non-alcoholic fatty liver disease

Non Alcoholic Fatty Liver Disease (NAFLD) is a clinicopathologic entity with wide histological spectrum which includes both simple steatosis and steatohepatitis (NASH). NAFLD is considered as the hepatic manifestation of the metabolic syndrome and is strongly associated with cardiovascular disease, while the most prevailing mechanism underlying the pathogenesis of NAFLD is insulin resistance. Nutrition is considered as an important component of both the pathogenesis and the treatment of NAFLD. The purpose of this review is to present all the existing data correlating dietary habits with the incidence of NAFLD, as well as clinical studies that include treatment by dietary intervention. Studies that have explored the role of diet in the pathogenesis of NAFLD are mainly case-control studies with retrospective data collection and do not reveal any prominent benefit or deficit of any of the macronutrients or their subclasses in the incidence of the disease. Moreover studies exploring the association between antioxidants intake and the risk of NAFLD remain contradictory. Regarding NAFLD management, weight loss for the overweight subjects is the cornerstone therapy weather it is achieved with diet alone or with a combination of diet and exercise. However, the impact of diet’s composition on the disease management remains uncertain. Based on the available evidence, there is a need for well designed prospective studies to explore the role of diet as a risk factor for NAFLD, as well as for randomized controlled clinical trials to define the best nutritional management for the disease.