In view of the epidemic obesity in childhood, facing the disease and its associated morbidities early at this age becomes crucial for public health researchers and care givers. The present review focuses on pediatric Non Alcoholic Fatty Liver Disease (NAFLD) among co-morbidities, being the disease yet under diagnosed and under treated despite a prevalence growing exponentially. Evidences suggest that the environmental background for the development of NAFLD may be established in early life, and that the duration of the disease affects probably the likelihood of progression to more severe disease (necro-inflammation or Non Alcoholic SteatoHepatitis, also termed, NASH; fibrosis and cirrhosis). NAFLD associates with abdominal obesity, insulin resistance and features of metabolic syndrome. In genetically prone individuals, malnutrition (i.e., excessive consumption of saturated fats and refined sugars) leads to the derangement of the adipose tissue architecture and homeostasis, the peripheral and hepatic resistance to insulin-stimulated glucose uptake, thus favoring a condition of chronic low-grade inflammation. Excessive nutrients cannot be stored in the adipose tissue and overflow elsewhere, mainly to the muscle tissue and liver. Fat deposition in both sites enhances insulin resistance and further deposition of fats in a vicious manner. What is of special interest comparing NAFLD in children and adults is that the histological appearance of the disease differs significantly, likely representing a yet physiological response to environmental stressors in children and a long-term adaptation in adults. In this article, we review the current concepts about paediatric NAFLD, its pathogenesis, diagnosis and treatment, with particular regard to lifestyle and foods habits.