Supplemental Calcium Alone May Not Benefit Children's Bones

HOBART, Tasmania—Calcium may not be as effective as once thought in improving bone mineral density (BMD) in children or later in life among people given calcium as children, according to a study published in the British Medical Journal (Epub Sept. 15, 2006; DOI:10.1136/bmj.38950.561400.55). The randomized, placebo-controlled trial of calcium supplementation included 2,859 healthy children, ages 3 to 18, for three months. At six months, two reviewers independently extracted data and assessed quality; meta-analyses predominantly used fixed effects models with outcomes given as standardized mean differences. There was a small effect on total body bone mineral content (standardized mean difference 0.14, 95 percent confidence interval 0.01 to 0.27 and upper limb bone mineral density 0.14, 0.04 to 0.24). This effect persisted after the end of supplementation only at the upper limb (0.14, 0.01 to 0.28).

Children taking the calcium had only slightly better BMD in their upper arms--1.7 percent increase--compared to those not taking the supplements. "It had been thought that calcium supplements would be more helpful than that in children," said Tania Winzenberg, a musculoskeletal epidemiologist at the Menzies Research Institute here. "So, giving calcium supplements to children has little effect on fractures, and a fracture is what we worry about."

Based on the findings, Winzenberg's group recommends other approaches to improving kids' bone health, especially increasing vitamin D intake and eating more fruit and vegetables. U.S. researchers seconded the suggestion. "Healthy children, with an adequate diet, may have all the calcium they need to build bone," said David L. Katz, Ph.D., associate professor of public health and director of the Prevention Research Center at Yale University School of Medicine. "Growing bone might need a combination of materials, such as calcium combined with vitamin D, to grow stronger." 

Share this article: Email, Slashdot, Digg, Del.icio.us, Yahoo!MyWeb, Windows Live Favorites, Furl
Add this article feed to: RSS, My Yahoo, Newsgator, Bloglines

Read Comments [1]