Great question… but we don’t know!
This is a question that almost all patients or their family ask us. Unfortunately, we don’t know the cause of hyperparathyroidism. Parathyroid tumors develop in every country at the same rate throughout the world. Hyperparathyroidism is more common in women three times more commonly in men so we think there is something related to the fluctuating hormone levels in women that contribute, but obviously, men get this too.
Something in the environment?
Sometimes people will ask if there was something in their diet, or some environmental exposure that could have caused it. However, there has never been any component of diet or any kind of exposure to anything in the environment that has been linked to the development of parathyroid tumors
Radiation exposure causes parathyroid tumors
Radiation to the neck will often result in a parathyroid tumor (or tumors) 20 or more years later. Radiation was used back in the 50’s and 60’s to treat infected tonsils and to treat some cases of acne. Some of those patients get a parathyroid tumor many years later. At the Norman Parathyroid Center, we operate on about one of these patients per week.
Radioactive iodine ablation of the thyroid
Radioactive iodine is used to kill thyroid glands in people who have a large thyroid (called a goiter), or for people with Grave’s disease (overactive thyroid), or for people who have thyroid cancer. Most people who have radioactive iodine to kill the thyroid will get a parathyroid tumor about 15 years later. We operate on one or two of these patients per week.
Lithium is a drug that is sometimes used to treat depression. People taking lithium for more than 5 years will often develop a parathyroid problem. This is the only drug that has been linked to the development of hyperparathyroidism.
The bottom line is that we don’t know what causes parathyroid glands to develop into a tumor in over 95% of cases. It just happens. And just because it happened once, does not mean it is going to happen again. If your surgeon looks at all your glands, the chance of you getting parathyroid disease twice is very low… less than 1%