Nonalcoholic fatty liver disease (NAFLD) is a common chronic liver disease whose prevalence has reached global epidemic proportions, both in adults and children (1). There is consistent clinical and epidemiological evidence supporting the assertion that NAFLD may progress from a benign histological stage characterized by hepatic triglyceride accumulation, also known as simple steatosis, to a more severe histological picture characterized by liver cell injury, a mixed inflammatory lobular infiltrate, and variable fibrosis named nonalcoholic steatohepatitis (NASH) (1).