Which gland makes a hormone that controls the level of calcium in the body?

Which gland makes a hormone that controls the level of calcium in the body?

• A. Parathyroid gland
• B. Thyroid gland
• C. Pancreas
• D. Adrenal gland

Answer: (A)

Calcium levels in the body are regulated mainly by a hormone from the parathyroid glands. When calcium is low, parathyroid hormone (PTH) is released and works to raise calcium by signaling bones to release calcium, increasing the kidneys’ reabsorption of calcium so it's not lost in urine, and promoting the production of active vitamin D (calcitriol) in the kidneys, which boosts calcium absorption from the gut. This system uses a feedback loop: low calcium triggers PTH release, and rising calcium levels suppress it.

While the thyroid gland makes calcitonin, which can lower blood calcium, its role in adults is not the primary regulator. The pancreas and adrenal glands don’t control calcium levels in the same direct way.