What are the Parathyroid Glands?

The parathyroid glands are small hormone producing glands in the neck that regulate the amount of calcium in the blood stream. Calcium is a vital element not only in our skeletal system, but also in the function of our muscular and nervous system. Although the parathyroid and thyroid glands share a similar name and are both part of the endocrine system, the parathyroid glands have a completely unique function in the body: Their sole purpose is to monitor the calcium level in the blood and produce a hormone that releases the calcium from the bones when needed.

The importance of the parathyroid glands comes from the vital role that calcium plays in the proper functioning of our body. Calcium is used to generate the electrical energy that nerve cells use to send impulses and communicate. Similarly, our muscles use calcium to allow them to contract when stimulated. We also store calcium in our bones, both to make them strong and to be used in the body when needed. In fact, calcium is so important to our proper functioning, it is believed to be the only element or mineral that has it’s own regulatory system.

The parathyroid glands work by monitoring the blood with calcium-sensing receptors and releasing the parathyroid hormone when the levels of calcium get too low. The parathyroid hormone, also known as PTH or parathormone, stimulates the body to break down part of the bones to release calcium into the blood stream. The bones function like a storage area for calcium, releasing it when PTH is present, and storing it when it is not. PTH also increases the absorption of calcium by activating vitamin D in the gastrointestinal area and promotes re-absorption of calcium by the kidneys.

In humans, the parathyroid glands are usually located in the neck, just behind the larger thyroid gland. In rare cases however, these glands can be inside the thyroid gland or even in the chest cavity. They are small kidney-shaped glands that are typically about the size of a grain of rice. Most commonly, there are four glands, two on each side of the neck. The number and location of the parathyroid glands can vary in individuals without major problems, as long as the proper functioning is present.

When the parathyroid glands are not functioning properly, there are a variety of problems that can result. For example, one or more of the glands may malfunction and start producing too much hormone; this is called parathyroid disease. The result is elevated calcium levels in the blood, which can lead to kidney stones, osteoporosis, fatigue, and even depression. In general, the proper amount of calcium in the blood helps us to feel healthy, and the parathyroid glands are a vital part of the system that allows this to happen.