The Thyroid & Calcium

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The thyroid gland also plays a role in regulating the calcium component of bone, which is important for bone strength.

Another hormone produced and released by the thyroid gland is calcitonin. When blood calcium levels are high, calcitonin causes calcium to move out of the blood and be absorbed and deposited into bone tissues.

Also part of this homeostatic loop, the parathyroid glands (four small glands located on the surface of the thyroid) produce and release parathyroid hormone (PTH), which has the opposite effect.

In response to low blood calcium levels, PTH increases blood calcium by a few different mechanisms, including the release of calcium from bone tissue.