Question

My calcium is 10.5 mg/dl, my PTH is 53 pg/ml, my Vit D 25-hydroxy is 21 ng/ml. My doctor wants to start me on Vitamin D daily. Everything I’ve read says not to treat the low Vitamin D, if this could be primary hyperparathyroidism. Not sure what to do! How is taking Vit D going to lower my calcium level? I am 47 years old.

Answer

Deva Boone, MD is the founder of the Southwest Parathyroid Center. As one of the most experienced parathyroid surgeons in the U.S., she has treated thousands of patients with parathyroid conditions.

Let’s summarize your results:

Calcium at 10.5 mg/dl is elevated for your age. PTH at 53 pg/ml is not suppressed, which is inappropriate for the elevated calcium level. Vit D 25-hydroxy at 21 ng/ml is on the lower side.

These numbers strongly suggest primary hyperparathyroidism (pHPT). In the context of pHPT, taking Vitamin D supplements is not the recommended course of action. Why? Because Vitamin D enhances calcium absorption from the intestines, and in someone with already elevated calcium due to pHPT, this could drive the calcium levels even higher.

Now, addressing your main concern: Vitamin D supplementation does not lower calcium levels. In your situation, it could in fact increase them. Your doctor may be focusing on the low Vitamin D rather than the complete picture.

The only cure for pHPT is surgical removal of the overactive parathyroid gland(s), not Vitamin D supplementation.

Hypercalcemia primary hyperparathyroidism Diagnosis Vitamin D Vitamin D deficiency