What hormone must be produced if calcium levels are too low and why is the production of this hormone can lead to osteoporosis?

When calcium levels are too low, the parathyroid hormone (PTH) is produced to increase calcium levels in the blood. PTH stimulates the release of calcium from bones, increases intestinal absorption of calcium, and promotes kidney reabsorption of calcium. However, prolonged high levels of PTH can lead to excessive bone resorption, weakening the bones and increasing the risk of osteoporosis. This condition results from a net loss of bone density over time.