What is Parathyroid Hormone?

When we discuss hormone replacement we typically talk about putting back what is missing. Whether insufficient, or out of balance inadequate hormone levels can cause all sorts of disruptions in our body. But not all hormones are so temperamental that we would consider monitoring or supplementing them. Some reliably perform their duties and almost never cause upset. Despite their importance to the body they are ignored and often their potential therapeutic value goes unnoticed.

For example, the parathyroid glands synthesize and secrete a hormone that is responsible for regulating the amount of calcium, vitamin D, and phosphorus in our bloodstream. The task of maintaining the level of calcium in our blood within a very narrow range is essential to our survival. Excess calcium is stored away in our bones and teeth to provide strength and serve as a reservoir when levels in the blood drop. The 1% of calcium found outside this is responsible for creating the electrical energy that allows us to function. It enables our muscles to contract, our nervous system to relay messages, and is responsible for every beat of our heart.

Fortunately, the four tiny parathyroid glands function properly in the vast majority of people. In very rare cases major surgery on the head or neck can result in what is typically a temporary state of hypoparathyroidism. Even less often an autoimmune disease or genetic disorder will cause absent or underactive parathyroid glands. Typically treatment for these conditions consists of vitamin D and calcium replacement along with frequent blood work, but not parathyroid hormone replacement.

And so you would assume there would never be a use for a parathyroid hormone replacement. Yet a synthetic version of the hormone is available and has an important application, just not in treating hypoparathyroidism. ForteoÒ (teriparatide) is a synthetic version of parathyroid hormone. It is a unique injectable medication used to treat certain types of osteoporosis. It mimics the activity of parathyroid hormone by promoting the restructuring of bone, in fact it actually helps to build new bone.

I wouldn’t typically think to supplement the body with hormones that are already present in sufficient amounts, but I recognize the utility of this drug in treating certain individuals. Looking at this example makes me believe it may be time to broaden our views on hormone replacement. In our search for the next miracle drug maybe we should spend less time creating something from nothing and more time learning from what nature has already perfected.