Calcitonin: What It Is, How It Works, and Why It Matters for Bone Health

When your body needs to lower blood calcium, it turns to calcitonin, a hormone produced by the thyroid gland that helps regulate calcium levels by slowing down bone breakdown. Also known as thyroid calcitonin, it’s one of the body’s natural tools to keep bones dense and prevent excessive calcium from flooding the bloodstream. While most people hear about estrogen or bisphosphonates for osteoporosis, calcitonin has played a quiet but important role for decades—especially for those who can’t tolerate other treatments.

Calcitonin works by telling bone cells called osteoclasts to slow down. These cells normally break down old bone tissue to release calcium into the blood. When calcitonin steps in, that process quiets down, letting bone-building cells take over. This makes it useful for conditions like osteoporosis, a condition where bones become fragile and prone to fractures due to loss of bone density, especially in postmenopausal women or older adults. It’s also used in rare cases of hypercalcemia, a dangerous spike in blood calcium often caused by overactive parathyroid glands or certain cancers. Unlike some drugs that force bone growth, calcitonin simply takes the brakes off bone loss—making it a gentler option for some patients.

Even though newer drugs like denosumab and teriparatide have taken center stage, calcitonin hasn’t disappeared. It’s still prescribed when patients have allergies, kidney issues, or simply don’t respond well to other therapies. Nasal sprays and injections were once common, and while usage has dropped, it remains a viable choice in specific clinical situations. You’ll also find it referenced in studies on bone pain relief after fractures—some doctors still use it to reduce discomfort in spinal compression fractures.

What you’ll find in the posts below isn’t just a list of articles about calcitonin—it’s a real-world look at how this hormone fits into broader health patterns. From how it interacts with other hormones like parathyroid hormone, to its role in managing rare bone disorders, to how it compares with more common treatments, these posts cut through the noise. You’ll see connections to calcium balance, thyroid function, and even how aging affects bone turnover. Whether you’re managing osteoporosis, researching side effects, or just trying to understand why your doctor mentioned calcitonin, this collection gives you the facts without the fluff.