context: You may know that low levels of calcium in your bones can cause osteoporosis. But what makes calcium levels dip? This can happen for many reasons, like not getting enough calcium and vitamin D in your diet. But sometimes it can be a problem with your parathyroid glands. Your parathyroids control how much calcium is in your bones and blood. When they aren't working the way they should, calcium levels can get out of whack. Since calcium is key to good bone health, this puts you at a higher risk of getting osteoporosis. Calcium helps you move muscles, clot blood, and send messages through nerves. It also builds and strengthens bone. Your body can't make its own calcium -- it has to get it from the food you eat or from supplements. When you aren't getting enough calcium, your body takes it from your bones. Over time, your bones get weak and brittle -- you get osteoporosis. But even a high-calcium diet can't get your body the calcium it needs if your parathyroids aren't working correctly. These four tiny glands just behind your thyroid work like a thermostat. They keep the calcium in your blood at a specific level like a thermostat keeps the air in your house at a specific temperature. When that thermostat is broken, your bones don't get the calcium they need. When your body needs calcium, parathyroids make a hormone called parathyroid hormone ( PTH). Your body reacts by absorbing more calcium from food and keeping it from leaving through your urine. If your body has absorbed all the calcium it can from food and your parathyroids are still making PTH, your bones will release calcium into your bloodstream. Your parathyroids stop making as much PTH when your blood has enough (or too much) calcium in it. The parathyroid can cause osteoporosis by making too much PTH, which eventually makes your body take calcium from your bones. This is called hyperparathyroid disease or hyperparathyroidism. This can happen for several reasons, including: â¢ A non-cancerous growth on one of the glands â¢ Two or more glands get too big â¢ A cancerous tumor (this is rare) You also can get hyperparathyroidism if something else is keeping your calcium levels low. Your parathyroids will work overtime making PTH if you have: â¢ Not enough vitamin D â¢ Kidney failure â¢ Problems absorbing calcium When you have hyperparathyroidism, you might have symptoms like: â¢ Body aches and pains â¢ Bone and joint pain â¢ Confusion and memory loss â¢ Frequent urges to go the bathroom â¢ Heartburn â¢ High blood pressure â¢ Kidney stones â¢ Nausea or vomiting â¢ No appetite â¢ Stomach pain â¢ Tiredness You also may break bones easily -- a sign of bone weakness and osteoporosis. Your doctor can tell if you have hyperparathyroid disease by first looking at the level of calcium in your blood. If it's high, he'll look at your levels of PTH. If that number is high, he may use a special scan to check for a growth on your parathyroid. If your symptoms are mild, your doctor may decide to wait and see if they get worse. Or you may take medications like estrogen and bisphosphonates to get your body to make less PTH so your bones can rebuild. However, the medication won't cure your hyperparathyroidism. If you have a growth on your parathyroid glands and have symptoms, your doctor probably will recommend surgery to remove it. Your symptoms should stop within a month of having it taken off. The growth usually doesn't come back. Since PTH causes calcium to be taken out of your bones, a lab-made version of the hormone may seem like an odd choice for treating bone loss. But studies show that taking this regularly can actually build new bone and make your bones stronger. You take this hormone therapy once a day by giving yourself a shot under the skin. You can take it in the leg or the stomach. Over time, it can make your bones denser, which lowers the chances that you'll break them.