The four tiny parathyroid glands are located just behind the thyroid gland in your neck. The parathyroid glands make hormones that help control calcium and phosphorous levels in the body, which in turn help make bones strong. But the hormones do other things as well. If there is too little calcium in your diet, the parathyroids make a hormone called parathyroid hormone, or PTH, which causes calcium to leave the bones and enter the bloodstream, where it can be used to assist nerves and muscles to do their jobs. Too much secretion of PTH can cause bone pain, kidney stones, increased urination and fatigue. BACK