Indeed, vitamin D sterol therapy suppresses PTH while increasing circulating FGF23 levels dramatically in patients with end-stage kidney disease;[13] however, the effect of this form of therapy on skeletal expression of FGF23, sclerostin, and DMP1 in the context of advanced kidney disease and secondary hyperparathyroidism remains unknown. Here, FGF23 is linked to secondary hyperparathyroidism.