context: Your body needs calcium from head to toe. But there are times when your body can have so much calcium that it's not good for you. A condition called hyperparathyroidism can cause such a situation to happen, where your levels of calcium in your blood and tissues are too high. And it has nothing to do with how much milk you drink. In your neck, there are four similar glands -- each about the size of a grain of rice -- called parathyroid glands. They make a hormone that helps keep your amount of calcium at just the right level. But when even one of those glands makes too much of the hormone, the result is hyperparathyroidism. The hormone, called parathyroid hormone, has three ways it can raise your calcium level: It can tell your bones to release some calcium, tell your small intestine to absorb more calcium into your bloodstream, or tell your kidneys to hang on to more calcium instead of sending it out of your body in your pee. There are two kinds of hyperparathyroidism: Primary. This means that your condition is caused by, or starts in, at least one of the parathyroid glands naturally making too much of the hormone that keeps your calcium levels in balance. Secondary. This means that some other disease or condition is to blame. The common trigger is low calcium levels in the blood, which prompts your body to release parathyroid hormone almost immediately. About 100,000 people in the U. S. develop this condition each year. People between the ages of 50 and 60, and women, are the most likely to have hyperparathyroidism. Primary hyperparathyroidism can happen due to: A noncancerous tumor in one of the parathyroid glands. This causes most primary cases. Two or more of the glands being too active and producing too much of the parathyroid hormone. Cancer of one of the glands. This is a very rare cause of primary hyperparathyroidism. Secondary hyperparathyroidism (apart from kidney failure) can happen if: Your body doesn't get enough calcium. You could have low calcium levels in your blood for different reasons. You might be too low on vitamin D, or your digestive system might have problems with absorbing calcium. It also often happens if you have chronic kidney disease. You have extremely low levels of vitamin D. This vitamin helps balance the amount of calcium in your blood, and it helps your digestive system absorb calcium. If you have primary hyperparathyroidism, you most likely don't have any symptoms. But if you do have symptoms, they are likely not severe. They include: Muscles that feel weaker than usual Fatigue and wanting to sleep more Pain in your joints and bones Depression But if you have a more severe form of primary hyperparathyroidism and your calcium levels rise, your symptoms also could include: Being constipated Feeling nauseated Throwing up Not feeling hungry Feeling confused or forgetting things You're more thirsty than usual You pee more often than normal You have pain on one side of your lower abdomen (if you have kidney stones) Your doctor will make the diagnosis based on blood tests. If the results show that you have high levels of parathyroid hormone and of calcium, then you have primary hyperparathyroidism. You'll then get: X-rays to check for broken bones in certain areas, including in your back Bone density tests to look for reduced bone mineral density, especially in your forearm Kidney ultrasound to look for kidney stones 24-hour urine calcium collection to check for any kidney problems Blood tests looking at how well your kidneys work and your levels of phosphate and vitamin D can suggest secondary hyperparathyroidism. If you have secondary hyperparathyroidism, your doctor may recommend supplements of vitamin D and calcium. If you have primary hyperparathyroidism and you have bothersome symptoms, you'll need surgery to remove the overactive parathyroid gland or glands. For example, if you have extremely high blood calcium levels, have had a broken bone (or fracture), or have kidney stones, your doctor will likely want you to have that operation. Even if you don't have symptoms, your doctor may recommend the operation, depending on how you together decide to treat the condition. You might get these benefits from the surgery: Improved bone density Fewer bone fractures Less chance of forming kidney stones Surgery cures primary hyperparathyroidism in 95% of cases. Choose a surgeon who has a lot of experience in parathyroid surgery. Like any operation, there can be complications, so talk with your doctor about the risks and benefits, what to expect during the recovery, and how long you'll be in the hospital. If you're not a candidate for surgery, you might just need: Routine exams by your doctor Blood tests Bone density tests If you and your doctor decide you don't need the surgery, you can: Track how much vitamin D and calcium you get through your diet. But don't deliberately cut down on calcium. Talk to you doctor about whether you should take supplements, and if so, how much. Drink lots of fluids, especially water. Enough water can help prevent kidney stones. Exercise . Regular exercise, especially strength training, keeps your bones strong. Don't smoke. Smoking means more bone loss. Avoid medicines that raise your calcium levels. Talk to your doctor if you're on such medications, in case you need a different prescription.