"Magnesium keeps calcium dissolved in blood. Without the proper balance of magnesium to calcium, about a 2:1 ratio, calcium ends up depositing in the kidneys and can create kidney stones, in coronary arteries where it can lead to clogged arteries, and in joint cartilage, rather than in bones where we need it most. The more calcium taken without the balancing effect of magnesium, the more symptoms of magnesium deficiency and calcium excess you are liable to experience," Dr. Dean says.