Calcium citrate trumps calcium carbonate in osteoporosis studies

November 22, 1999

DALLAS -- November 23, 1999--Three studies from UT Southwestern Medical Center at Dallas researchers show that calcium citrate is better absorbed than calcium carbonate and is effective at preventing osteoporosis in early post-menopausal women.

Osteoporosis -- or brittle-bone disease -- is a major health threat to 28 million Americans. About 10 million have the disease, and 18 million more are at increased risk due to declining bone density caused by loss of calcium within the bones. Forty percent of women and 13 percent of men will suffer a bone fracture due to osteoporosis in their lifetime.

"It is well-recognized that calcium supplements taken at the proper time can help prevent bone loss in elderly patients," said Dr. Khashayar Sakhaee, chief of mineral metabolism. "We are interested in seeing which formulation is most beneficial in preventing osteoporosis and in maintaining bone density in early post-menopausal women."

Two of the studies compared calcium citrate with calcium carbonate to see which was better absorbed. Sakhaee and colleagues published their analysis of data from 15 previously published randomized trials evaluating bioavailability (the amount of calcium absorbed from a supplement, rather than the amount of calcium a supplement contains) in the November-December issue of the American Journal of Therapeutics. The second study, published by Dr. Howard Heller, assistant professor of internal medicine, and collaborators, in the November issue of the Journal of Clinical Pharmacology compared the absorption of two over-the-counter calcium supplements -- Citracal (calcium citrate) with Os-Cal (calcium carbonate). The researchers used classic pharmacokinetic techniques of measuring peak and cumulative increase in blood calcium concentration over six hours following a single oral dose instead of the indirect method of measuring change in urine calcium excretion.

A third study, published by Sakhaee, former UT Southwestern faculty member Dr. Lisa Ruml and co-workers, also reported in the November-December issue of the American Journal of Therapeutics, compared the effect of calcium citrate vs. a placebo in preventing bone loss in early post-menopausal women.

All three studies confirmed the benefits of calcium citrate. The conclusion from the 15-trial analysis was that calcium citrate was absorbed 22 percent to 27 percent better than calcium carbonate when taken either on an empty stomach or with meals. Heller's study of commercial calcium preparations concluded that Citracal was more "bioavailable" than Os-Cal; it was absorbed faster and to a greater extent.

"Our results show that even under the most favorable conditions, calcium carbonate is not nearly as well-absorbed as calcium citrate," Heller said. "We were surprised at the magnitude of the difference in absorption rates -- with calcium citrate being absorbed two and a half times better than calcium carbonate."

The third study - the first of its kind - showed the benefits of calcium citrate in early post-menopausal women. During the two-year study, 57 women in early menopause (five years into menopause) and six mid-menopausal women (five to10 years into menopause) took either 800 milligrams of calcium citrate or a placebo daily. Those taking calcium citrate averted bone loss by stabilizing the bone density in their spine, in the top part of the thigh bone (a common site of hip fractures) and in the small bone of the forearm. Women taking the placebo had a significant decrease over the two-year period in the densities of the spine and forearm, but showed no change in thigh-bone density.

"This study shows that calcium-citrate treatment may be used alone in the prevention of skeletal bone loss in early post-menopausal women," said Sakhaee. "The long-term effectiveness of calcium citrate is a particularly exciting therapeutic finding."

UT Southwestern mineral metabolism researchers developed Citracal in conjunction with Mission Pharmacal of San Antonio.
-end-
his news release is available on our World Wide Web home page at http://www.swmed.edu/home_pages/news/

To automatically receive news releases from UT Southwestern via e-mail, send a message to UTSWNEWS-REQUEST@listserv.swmed.edu . Leave the subject line blank and in the text box, type SUB UTSWNEWS

UT Southwestern Medical Center

Related Osteoporosis Articles from Brightsurf:

New opportunities for detecting osteoporosis
Osteoporosis can be detected through low dose computed tomography (LDCT) imaging tests performed for lung cancer screening or other purposes.

Oxytocin can help prevent osteoporosis
In a laboratory experiment with rats, Brazilian researchers succeeded in reversing natural processes associated with aging that lead to loss of bone density and strength.

New strategy against osteoporosis
An international research team has found a new approach that may be able to reduce bone loss in osteoporosis and maintain bone health.

New review on management of osteoporosis in premenopausal women
An IOF and ECTS Working Group have published an updated review of literature published after 2017 on premenopausal osteoporosis.

Cardiac CT can double as osteoporosis test
Cardiac CT exams performed to assess heart health also provide an effective way to screen for osteoporosis, potentially speeding treatment to the previously undiagnosed, according to a new study.

Osteoporosis treatment may also protect against pneumonia
A recent study published in the Journal of Bone and Mineral Research found that nitrogen-containing bisphosphonates (N-BPs) such as alendronate, which are widely used to treat postmenopausal osteoporosis, are linked with lower risks of pneumonia and of dying from pneumonia.

New pharmaceutical target reverses osteoporosis in mice
Biomedical engineers at Duke University have discovered that an adenosine receptor called A2B can be pharmaceutically activated to reverse bone degradation caused by osteoporosis in mouse models of the disease.

A link between mitochondrial damage and osteoporosis
In healthy people, a tightly controlled process balances out the activity of osteoblasts, which build bone, and osteoclasts, which break it down.

Many stroke patients not screened for osteoporosis, despite known risks
Many stroke survivors have an increased risk of osteoporosis, falls or breaks when compared to healthy people.

Many postmenopausal women do not receive treatment for osteoporosis
The benefits of treating osteoporosis in postmenopausal women outweigh the perceived risks, according to a Clinical Practice Guideline issued today by the Endocrine Society.

Read More: Osteoporosis News and Osteoporosis Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.