In recent years, there has been strong and convincing evidence that calcium is important for building strong bones in childhood, maintaining bone density in adults, and reducing the likelihood of fractures as we age. Just about every cell in the body, including those in the heart, nerves and muscles, relies on calcium to function properly.
Bones require calcium to maintain their strength.
It is the blood flowing through bodies that carries calcium to the organs and cells where it is needed. This is the preferable way for the body to get calcium. It takes calcium from your bones if there is not enough available when it is needed. When this happens, the bones become thinner and more fragile. It slows down the amount of calcium that leaves the body in the urine by returning some to the blood stream where it remains available to organs and cells.