Non-alcoholic fatty liver disease (NAFLD) is one of the most frequent causes of chronic liver disease in the Western world, probably due to the growing prevalence of obesity, metabolic diseases, and exposure to some environmental agents. In certain patients, simple hepatic steatosis can progress to non-alcoholic steatohepatitis (NASH), which can sometimes lead to liver cirrhosis and its complications including hepatocellular carcinoma. Understanding the mechanisms that cause the progression of NAFLD to NASH is crucial to be able to control the advancement of the disease. The main hypothesis considers that it is due to multiple factors that act together on genetically predisposed subjects to suffer from NAFLD including insulin resistance, nutritional factors, gut microbiota, and genetic and epigenetic factors. In this article, we will discuss the epidemiology of NAFLD, and we overview several topics that influence the development of the disease from simple steatosis to liver cirrhosis and its possible complications.

中文翻译：

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非酒精性脂肪肝疾病：代谢，遗传，表观遗传和环境危险因素

非酒精性脂肪性肝病（NAFLD）是西方世界慢性肝病最常见的原因之一，可能是由于肥胖，代谢性疾病和某些环境因素的日益流行所致。在某些患者中，单纯性肝脂肪变性可发展为非酒精性脂肪性肝炎（NASH），有时可导致肝硬化及其并发症，包括肝细胞癌。了解导致NAFLD演变为NASH的机制对于控制疾病的进展至关重要。主要假设认为这是由于多种因素共同作用于遗传易感性NAFLD受试者，包括胰岛素抵抗，营养因素，肠道菌群以及遗传和表观遗传因素。在本文中，