Rainy Day Savings
We human beings need calcium in our blood--it allows us to do all sorts of neat things, from contracting muscles to conducting nerve impulses. Where to get some calcium? Food is a good idea.
But there isn't always calcium-rich food to be had, which is why our body stores up extra calcium in our bones. Then, when the blood runs low on calcium, a signaling device called the parathyroid gland can activate a process by which calcium is taken from the skeleton and put back into the bloodstream.
Bone To Pick
This is a great short-term fix, but eventually the skeleton will suffer from the loss of its own calcium--bones will become brittle.
Prevent osteoporosis by helping your body get more calcium now. Eat fatty fish and vitamin-D rich dairy products. Vitamin D causes the small intestine to increase its calcium uptake, bypassing the need to grab extra from the bones. Under a doctor's supervision, calcium tablets might also be helpful, along with the old standard--more exercise. Weight-bearing exercise helps keep bones strong and less likely to fall prey to the body's own mechanisms in later age.
"Restoring Aging Bones" (Scientific American)