Don't Overdose on Calcium

By: Jean Carper

Many Americans megadose on calcium, certain it will strengthen bones and prevent fractures and osteoporosis.

That's a myth. Taking calcium may help "only temporarily," says Katherine Tucker, of the USDA Human Nutrition Research Center on Aging at Tufts University. "If you stop, bones regress fast." Taking 1,200-1,500 milligrams of calcium supplements a day, as commonly recommended, may be unnecessary, she says: "A 700 to 800mg daily supplement is usually enough." Adding just 500mg of calcium a day benefits bone density.

Harvard nutritionist Walter Willett agrees that an extra 500-1,000mg calcium daily (combined in supplements and food) may add calcium to bones, but after a year or so, continued high calcium probably does not further build bone density.

Moreover, experts say, overdoing calcium can have side effects, such as unbalancing magnesium, which may promote heart problems.

No one really knows the right dose, Willett says. The Institute of Medicine puts the upper tolerable (or safe) dose at 2,500mg daily, from food and supplements.

Notes Willett: "Countries with the highest average calcium intake tend to have higher, not lower, hip fracture rates." Bone health is far more complex than calcium alone, involving many nutrients and genetics, says new research.

Tucker's bottom line to protect bones: Eat a balanced diet rich in fruit, vegetables, whole grains, milk, chicken and fish, and low in junk food and cola. A low-dose daily supplement of calcium may help, but don't count on it as a bone-saving magic bullet.

For more information from Jean Carper, go to www.Jeancarper.com