What is calcium?
Calcium is a mineral that primarily functions in your body by making your bones and teeth hard. The rest is in your blood and soft tissues; it helps your muscles contract and your blood clot, and helps your nervous system work properly.
How much calcium do you need?
There is a conflict between the U.S. Recommended Dietary Allowance and what the dairy advocates would have you do; the latter bases its numbers on a National Institutes of Health symposium on calcium consumption.
| |
RDA
|
NIH
"Optimal Calcium Intake"
|
| Adults |
800 mg |
1,000 mg |
| Adults over 65 |
N/A |
1,500 mg |
| Pregnant and nursing women |
1,200 mg |
1,200 mg |
| Young adults (11-24) |
N/A |
1,200-1,500 mg |
| Children under 11 |
800 mg |
800-1,200 mg |
Is it possible to take too much calcium?
According to the National Institutes of Health, yes. Although it should be safe for adults to consume up to 2,000 mg of calcium every day without adverse side effects, the institute says, going over that may lower the absorption of certain medications, such as tetracycline, and of some nutrients, including iron. Overuse of calcium carbonate (available commercially as the active ingredient in Tums and other antacids) can also lead to severe renal damage and other problems related to calcium toxicity.
Calcium and kidney stones
Some studies have indicated that men with a history of kidney stones may make the problem worse by increasing their intake of calcium. In other studies, men with low calcium intake suffered fewer kidney stones when they consumed more calcium. The NIH says more study on the calcium-kidney stone link is needed.
Calcium and osteoporosis
Getting enough calcium is one of the best ways to prevent osteoporosis, a debilitating disease in which the bones deteriorate and take a long time to heal. One-half to one-third of post menopausal women will get varying degrees of osteoporosis; of the 25 million Americans with osteoporosis, one in five is male.
