(2021) pointed out that β-Klotho itself is not only an ‘ essential switch ‘ of FGF19/21 signal, but also may become an independent therapeutic target: increasing the expression of β-Klotho through small molecule drugs or gene regulation can not only enhance the efficacy of FGF21 drugs, but also directly improve insulin resistance, blood glucose and lipid metabolism abnormalities (20). Here, FGF21 is linked to Insulin resistance.