Ιn meta-regression analysis, male ratio was positively associated with TNF-α in the comparison between patients with NASH and NAFL and could explain 36% of the heterogeneity in this comparison [50]; therefore, the male to female ratio may influence the association between TNF-α levels and NAFLD, which should be taken into account in the design of relevant future studies. Here, TNF is linked to non-alcoholic fatty liver.