Calcium Supplement Options

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Calcium Supplement Options

Question:

What's the difference between calcium carbonate and calcium citrate? What should your supplement contain to help prevent osteoporosis?

Answer

There are many forms of calcium supplements. When it comes to bone health, the differences are minor. The most important thing is that you get enough calcium, not that you take a particular type. Cost and side effects are the important factors.

Calcium carbonate, found in TUMS and Caltrate, provides more calcium per pill than calcium citrate. You may be able to take fewer pills of calcium carbonate. Extra acid helps with the absorption of calcium carbonate, so take it with orange juice or just after a meal. An added benefit of calcium carbonate is that it may relieve upset stomach. However, some people have stomach cramping or a bloated sensation when they use calcium carbonate.

Calcium citrate, found in Citracal and other supplements, tends to be easier to absorb, so you can take it any time of day. However, it contains a bit less calcium than calcium carbonate. You may need to take more pills each day if you use calcium citrate.

Side effects that may accompany any calcium supplement include allergic reactions, nausea, loss of appetite, constipation, dry mouth, increased thirst or increased urination.

If your diet contains enough calcium, you may not need to take a supplement. The recommended daily intake for an adult is 1,000 to 1,200 mg a day. Foods with 200mg to 300mg of calcium per serving include milk, yogurt, and fortified orange juice. Current estimates suggest that at least half the American population (including children and teenagers) is not getting enough dietary calcium, so supplements make sense for many people.

Talk to your doctor about your diet and whether it's important that you take calcium supplements. If you do, calcium carbonate and calcium citrate are both excellent options.

Robert Shmerling, M.D., is associate physician and clinical chief of rheumatology at Beth Israel Deaconess Medical Center and an associate professor in medicine at Harvard Medical School. He is an active teacher in the Internal Medicine Residency Program, serving as the Robinson Firm Chief. He is also a teacher in the Rheumatology Fellowship Program and has been a practicing rheumatologist for over 25 years.

Last updated:	July 20, 2009