Phosphorus and calcium are two minerals that
are needed to build strong bones. They also help nerves and muscles work. These minerals
are both found in the bloodstream where they have an inverse or "see-saw"
relationship; when one goes up, the other goes down.
The balance is normally controlled by the kidneys. But when they fail,
phosphorus tends to build up in the bloodstream causing the calcium level to drop. Calcium
is then released from the bones into the bloodstream. This increases the level of calcium
in the blood, but causes bones to become brittle from a lack of calcium there. The result
of this see-sawing back and forth can be easily fractured and broken bones.
