A balanced view of calcium and phosphate homeostasis in chronic kidney disease  Pieter Evenepoel, Myles Wolf  Kidney International  Volume 83, Issue 5, Pages 789-791 (May 2013) DOI: 10.1038/ki.2013.21 Copyright © 2013 International Society of Nephrology Terms and Conditions

Figure 1 Schematic of the proposed temporal aspects of calcium balance in chronic kidney disease (CKD) without and with calcium supplementation. (a) Patients with CKD who habitually consume a low-calcium diet (bottom) are in negative calcium balance due to impaired gastrointestinal absorption (middle). Negative calcium balance leads to secondary hyperparathyroidism and progressive bone demineralization (top). (b) With high-dose calcium supplementation (bottom), calcium balance becomes positive, but the magnitude of positivity is greatest early after the initiation of supplementation and wanes with time (middle). During the initial phase of positive calcium balance, bone is the primary site of calcium deposition, but prolonged supplementation can lead to a gradual shift toward relatively greater soft tissue deposition (top). The amounts of dietary calcium intake and calcium supplementation, use of vitamin D sterols, and the severity and duration of CKD and secondary hyperparathyroidism are several factors that will influence calcium balance and the distribution of its tissue deposition. Kidney International 2013 83, 789-791DOI: (10.1038/ki.2013.21) Copyright © 2013 International Society of Nephrology Terms and Conditions