Further, UDCA was found to improve NASH, insulin resistance, and high-fat diet (HFD)-induced obesity through suppression of FXR signaling, which is manifested by a significant reduction of FXR and fibroblast growth factor 19 (FGF19) levels coupled with elevation of cholesterol 7α-hydroxylase (CYP7A1) expression in the intestine (17). Here, FGF19 is linked to obesity due to melanocortin 4 receptor deficiency.