VDR and chronic kidney disease: NVD supplements might be considered as the adjuvant therapy for SHPT prevention in not yet HD patients for the following reasons: (1) High prevalence of VDD in CKD patients; (2) NVD is the substrate for 1α-hydroxylase, whose activity is increased in SHPT; (3) 25D directly interacts with VDR in PTG; (4) NVD is relatively inexpensive and has a lower risk of toxicity, hypercalcemia, and hyperphosphatemia; and (5) NVD had a pleiotropic effect in our previous reports [46].