Why is vitamin D therapy given to dialysis patients?

• A. Vitamin D reduces phosphate levels
• B. Vitamin D improves red blood cell production
• C. Vitamin D is needed for healthy bones
• D. Vitamin D helps with calcium absorption

Answer: (C)

Vitamin D therapy in dialysis patients is used to support bone health. In kidney failure, the body can’t activate vitamin D, which leads to lower calcium absorption, higher phosphate levels, and secondary hyperparathyroidism that weakens bones. Giving active vitamin D or its analogs helps restore calcium absorption and suppress parathyroid hormone, reducing bone turnover problems and preventing renal osteodystrophy. While vitamin D does influence calcium absorption, the primary purpose in this setting is maintaining healthy bones. The other ideas—directly lowering phosphate, or boosting red blood cell production—aren’t the main goals of vitamin D therapy.