Excessive serum levels of FGF21 were reported in atherosclerosis patients with ischemic heart disease as well as in non-alcoholic fatty liver disease, type 2 diabetes, and metabolic disorders (Shen et al., 2013; Kim et al., 2015; Xiao et al., 2015; Wu et al., 2020). Here, FGF21 is linked to type 2 diabetes mellitus.