Ask Peggy

Can you consume too much calcium?

DEAR PEGGY: Are calcium supplements or calcium-fortified foods a good substitute for dairy foods? Can you consume too much calcium? —N.K., Dayton, Maryland

It is never too late to enjoy the benefits of calcium-rich foods, even if you're just beginning to increase your calcium intake. For adults age 51 and older, calcium remains important for bone health as well as for protection against high blood pressure and cancer.

One cup of plain nonfat yogurt offers 450 milligrams of calcium, and an 8-ounce glass of fat-free milk contains 300 milligrams. However, most adults (up to 50 years old) need roughly 1,000 milligrams a day. This is where supplements and fortified foods such as juice, cereal, pasta and rice can help.

In general, if you choose the right foods, you should be getting an adequate amount of calcium. Calcium-fortified foods and supplements can help fill in the gap if the foods you are eating don't quite total the recommended amount.

Fortified foods and supplements are meant to round out—not replace—foods with naturally occurring calcium. You should not substitute them for dairy products because they do not supply all of the nutrients found in those items. For example, foods in the milk group are key sources of calcium as well as protein and vitamins A, B2, B12 and D (if fortified). Similarly, these foods also offer the minerals phosphorus, potassium, magnesium and zinc.

There is a slight possibility that you can overdo it on calcium if you take daily calcium supplements and regularly consume fortified foods such as breakfast cereal and juice. Doing so may limit the body's absorption of iron and zinc—two minerals that many Americans are short on to begin with.