An Overview of the Parathyroid

The Calcium-regulating Gland that Helps Keep Bones Healthy

Written by Robert M. Sargis MD, PhD

Parathyroid Glands: Essentials

The parathyroid glands are four small glands that have the sole purpose of secreting parathyroid hormone to regulate the calcium level in our bodies.
The parathyroid essentially helps the nervous and muscular systems function properly. Calcium is the primary element that causes muscles to contract, and calcium levels are very important to the normal conduction of electrical currents along nerves.
Anatomy of the Parathyroid Glands
The four parathyroids are typically found on the back side of the thyroid. They’re about the size and shape of a grain of rice.
Although the parathyroids are very close to the thyroid gland anatomically, they have no related function. The thyroid gland regulates the body’s metabolism, while parathyroid glands regulate calcium levels and have no effect on metabolism.
Parathyroid Hormone
Parathyroid hormone (PTH) has a very powerful influence on the cells of your bones by causing them to release their calcium into the bloodstream. 
Diseases and Disorders of the Parathyroid
When the parathyroid releases too much or too little PTH, it adversely affects your body in a variety of ways. Below are common diseases and disorders associated with the parathyroid glands:
The parathyroid glands have a single responsibility—regulating calcium levels. The glands are important members of endocrine system, but they are also integral to the proper functioning of the nervous and muscular systems.