Confused About Calcium Supplements?

Are you getting enough calcium in your diet? Maybe not, especially if you're a woman or a teenage girl. Although Americans have improved at this in recent years, we're still not getting enough calcium to maintain our bone health.

How much is that? It depends on your age. According to the Institute of Medicine, the recommended daily amount of calcium to get is:

• 1-3 years: 700 milligrams daily
• 4-8 years: 1,000 milligrams daily
• 9-18 years: 1,300 milligrams daily
• 19-50 years: 1,000 milligrams daily
• 51-70 years: 1,200 milligrams daily for women; 1,000 milligrams daily for men
• 71 and older: 1,200 milligrams daily

The Institute of Medicine says that most in the U.S. get enough calcium, except for girls 9 to 18 years old. Although women’s recommended calcium needs to increase with menopause, postmenopausal woman taking supplements may also be at greater risk of getting too much calcium.

"We know that peak bone mass occurs around age 30, so it's very important in childhood and adolescence to have a healthy intake of calcium early on," says Marcy B. Bolster, MD. She is a professor of medicine in the division of rheumatology and immunology at the Medical University of South Carolina and director of the MUSC Center for Osteoporosis and Bone Health.

"After age 30, we start to gradually lose bone, and that loss accelerates for women at the time of menopause. So it's very important to stave off bone loss with adequate calcium intake."

Your health care provider may recommend calcium supplements. But with so many choices of calcium supplements, where should you start? Here's what you need to know.

What kind of calcium supplement should you take?

"I tell my patients to take the kind that they tolerate best and is least expensive," Bolster says. She says she recommends calcium carbonate because "it's inexpensive, won't cause discomfort, and is a good source of calcium."

Some people's bodies may have problems making enough stomach acid, or may be taking medications that suppress acid production. For them, says J. Edward Puzas, MD, a calcium citrate supplement might be better because it "dissolves a little better than calcium carbonate for these people." Puzas is a professor of orthopedics and director of orthopedic research at the University of Rochester Medical Center in New York.

What about other types of supplements, like calcium plus magnesium, coral calcium, and so on? Not necessary, the experts tell WebMD. But they note that supplements that combine calcium with vitamin D -- which is essential for the body to appropriately absorb calcium -- provide an added benefit.

What calcium supplement dose is best?

The body can absorb only about 500 milligrams of a calcium supplement at any one time, says Puzas, so you can't just down a 1000-mg supplement first thing in the morning and call it a day.

Instead, split your dose into two or three servings a day. "The best way to take it is with a meal; calcium is absorbed better that way," Puzas says. If your daily diet includes calcium-containing foods and drinks, you may not need multiple doses.