There were no significant differences in alanine aminotransferase (ALT), aspartate transaminase (AST) and triglyceride (TG) levels among the groups, whereas the serum levels of FFA and IL-1β were significantly higher in the NASH patients compared with the normal healthy controls and NAFL patients, thus suggesting that the FFA and IL-1β levels are mainly associated with NASH but not NAFL. This evidence concerns the gene IL1B and non-alcoholic fatty liver.