A Controlled Trial of the Effect of Calcium Supplementation on Bone Density in Postmenopausal Women

Abstract

Background. The effectiveness of calcium in retarding bone loss in older postmenopausal women is unclear. Earlier work suggested that the women who were most likely to benefit from calcium supplementation were those with low calcium intakes. Methods. We undertook a double-blind, placebo-controlled, randomized trial to determine the effect of calcium on bone loss from the spine, femoral neck, and radius in 301 healthy postmenopausal women, half of whom had a calcium intake lower than 400 mg per day and half an intake of 400 to 650 mg per day. The women received placebo or either calcium carbonate or calcium citrate malate (500 mg of calcium per day) for two years. Results. In women who had undergone menopause five or fewer years earlier, bone loss from the spine was rapid and was not affected by supplementation with calcium. Among the women who had been postmenopausal for six years or more and who were given placebo, bone loss was less rapid in the group with the higher dietary calcium intake. In those with the lower calcium intake, calcium citrate malate prevented bone loss during the two years of the study; its effect was significantly different from that of placebo (P less than 0.05) at the femoral neck (mean change in bone density [+/- SE], 0.87 +/- 1.01 percent vs. -2.11 +/- 0.93 percent), radius (1.05 +/- 0.75 percent vs. -2.33 +/- 0.72 percent), and spine (-0.38 +/- 0.82 percent vs. -2.85 +/- 0.77 percent). Calcium carbonate maintained bone density at the femoral neck (mean change in bone density, 0.08 +/- 0.98 percent) and radius (0.24 +/- 0.70 percent) but not the spine (-2.54 +/- 0.85 percent). Among the women who had been postmenopausal for six years or more and who had the higher calcium intake, those in all three treatment groups maintained bone density at the hip and radius and lost bone from the spine. Conclusions. Healthy older postmenopausal women with a daily calcium intake of less than 400 mg can significantly reduce bone loss by increasing their calcium intake to 800 mg per day. At the dose we tested, supplementation with calcium citrate malate was more effective than supplementation with calcium carbonate.

The acid-base hypothesis: diet and bone in the Framingham Osteoporosis Study

“…Based largely on experimental studies, there is general agreement that calcium and vitamin D are important nutrients to bone health, and supplements containing calcium and vitamin D are widely prescribed to prevent osteoporosis and hip fracture [1][2][3]. The recent large increase in recommended calcium intake (from 800 mg recommended dietary allowance (RDA) to 1,200 mg defined as adequate intake (AI) for adults aged 51 years and older, for example) is primarily designed to protect bone status, based on studies of maximal calcium retention [4].…”

Zoledronic acid for treatment of osteopenia and osteoporosis in women with primary breast cancer undergoing adjuvant aromatase inhibitor therapy: a 5-year follow-up

“…While ZA is generally considered a potent bisphosphonate, a recent meta-analysis has found a mortality benefit in breast cancer patients using bisphosphonates, regardless of sub-type, elevating the importance of convenience and toxicity profile when deciding on a particular agent [25]. It should be noted that patients in this study received, in addition to ZA, calcium and vitamin D supplementation, which has been shown to decrease bone loss in healthy postmenopausal women with osteoporosis [26][27][28][29][30]. To our knowledge, no study has been specifically designed to evaluate the efficacy of calcium and vitamin D in preserving BMD in postmenopausal women with osteoporosis who are initiating AI therapy.…”

Primary osteoporosis prophylaxis with different calcium preparations

“…Назначение препаратов кальция и витамина D привело к повышению М П КТ в поясничном отделе позвоночника, причем более выраженное -у ж енщ ин после 60 лет, что со гласуется с данными, полученными в других исследовани ях [9,14]. Однако наши данные противоречат результатам, полученным Л.Я.…”