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My brother is 33 years old. Last year his calcium level was 10.4 mg/dl and this year its 10.3. Should we be concerned since it is above 10? Should we request the doctor to do more lab tests?

Deva Boone
Answer authored by Deva Boone
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.

At 33 years old, a calcium of 10.3 mg/dl can be normal. It’s on the higher end of normal, but still normal. It’s always a good idea to look at prior labs, so the calcium from last year is helpful. If possible, it would be good to see any prior labs also. If his calcium was in the 9s throughout his 20s, but is now in the 10s, then that would be concerning for primary hyperparathyroidism. If his calcium has been in the 10s throughout his 20s, then his current labs look normal.

Typically calcium levels go down as you age. For most adults, by the time they are in their 40s, the calcium level is in the 9s (mg/dl). Most people in their 30s will also be in the 9s, but some will have calcium levels in the 10s, which gradually drop into the 9s over time.

If he is concerned about parathyroid disease (because of symptoms or other health issues), it would be reasonable to check PTH and Vitamin D 25-OH levels in addition to repeating the calcium. If the PTH is high and the calcium is still in the low 10s, then that could be primary hyperparathyroidism.

Most likely, these calcium levels are normal for him. But if he is concerned about parathyroid disease, have him request calcium, PTH, and Vitamin D levels.

Normal calcium Primary HPT Diagnosis