[ kal-suh-tow-nuhn ]

Calcitonin is a hormone that is produced in the thyroid gland and plays a role in regulating calcium levels in the body. It works by inhibiting the activity of cells called osteoclasts, which break down bone tissue and release calcium into the bloodstream. By decreasing the activity of osteoclasts, calcitonin helps to reduce the amount of calcium in the bloodstream, which can be beneficial in certain conditions such as osteoporosis.