What are parathyroids?

Control calcium: They are four tiny glands that regulate the calcium metabolism in the body. They sit behind the thyroid and share some of the same blood supply, but have a totally different function than the thyroid.Hyperparathyroidism is relatively common and is picked up when the calcium levels in your body are high. It can cause kidney stones, bone pain, fatigue, memory loss, and probably cardiovascular diseas.

Endocrine glands: Two on each side in most people. They secrete PTH and control the blood calcium very accurately.