Although NAFLD is closely linked to obesity, NAFLD can develop in patients who are not obese. The severity and clinical outcomes of NAFLD in non-obese individuals have now been investigated. 307 patients with NAFLD were recruited for the study (23.5% were not obese). Compared with patients who were obese, those who were not obese had lower NAFLD activity scores, lower fibrosis stage and lower liver stiffness measurement. Thus, these patients have less severe disease than their counterparts with obesity. Hypertriglyceridaemia and high creatine levels are associated with advanced liver disease in patients with NAFLD who are not obese.