Your bones store minerals and release them when the body needs a steady supply.

The longer version

Bone acts as a reservoir as well as a framework, holding large amounts of calcium and phosphate locked into its mineral crystals. When the level of calcium in the blood drifts, hormones respond: one type stimulates cells that dissolve bone and release mineral into the bloodstream, while another encourages cells that deposit it back into the matrix.

The exchange happens continuously in healthy bone as part of normal remodelling, not only during shortage. Because the skeleton holds the body's largest store of these minerals, it buffers short-term changes in supply. The same system also repairs microdamage, linking mineral balance to structural maintenance. Nerves and other tissues depend on that steady circulating level, which the skeleton helps maintain.

Where this entry sits

These facts look at how the human body works in ordinary moments, from breathing and blinking to balance and sleep. They focus on anatomy, senses, and small reactions that happen constantly without any conscious effort. The full list sits on the Human Body page, where every entry is listed in order.