FGF23 suppresses the production of 1,25(OH)2D from the kidney due to decreased 1α hydroxylation of 25-hydroxy vitamin D. The resulting low concentrations of 1,25(OH)2D lessen the suppression of the parathyroid glands by this active form of vitamin D5, leading to the enhanced secretion of PTH, and also the induction of hypocalcaemia bydecreasing calcium absorption from the colon19. Here, PTH is linked to Hypocalcemia.