Power of Vitamin D: A Vitamin D Book That Contains The Most Scientific, Useful And Practical Information About Vitamin D - Hormone D

If you are taking high doses (10,000 IU a day) your doctor must do a blood test to check your calcium, phosphorous, and parathyroid

Monitoring your vitamin D blood level (25 OH vitamin D) is necessary to be sure you are not on too little or too much. It should be part of every checkup with your doctor.