Calcium Supplements in Kids Overrated?
Children Who Get Calcium-Fortified Foods or Pills Don't Develop Stronger Bones, Study Shows
April 18, 2006 -- Most kids who take calcium supplements -- or eat calcium-fortified foods -- don't get stronger bones, a review of clinical studies shows.
The review, by Tania Winzenberg, MD, and colleagues at Australia's Menzies Research Institute, analyzed data from 19 studies of calcium supplements in children aged 3 to 18 years. The researchers selected only studies that tested calcium supplements against inactive placebo and included measurements of bone densitybone density. The time frames of the studies were between 8.5 months and seven years.
Pooled data on all 2,859 children in the studies showed that calcium supplements had very little, if any, effect on children's bone density.
"There is 'gold' level evidence that calcium supplements may not help to build stronger bones in children enough to make a difference in the risk of breaking a bone," Winzenberg and colleagues write. "The results of this review do not support the use of calcium supplements in healthy children."
The findings appear in the current issue of The Cochrane Library. It is published by the Cochrane Collaboration, an international effort to evaluate health care research based on stringent criteria.
The studies of calcium supplements included studies of calcium pills as well as calcium extracted from milk and added to foods.
"We found there wasn't much effect at all," Winzenberg told the Health Behavior News Service. "It does challenge what we thought we knew."
Kids Need Calcium
Kids' bone density is a major factor in how easily they fracture bones. But that's small potatoes compared to the lifelong consequences of too-low bone density. From the time people enter puberty until the time they are young adults, they build up essentially all the bone they ever will have. Low bone density during late childhood predicts osteoporosisosteoporosis in later life.
Childhood fracture rates are up -- a sign that kids aren't building strong enough bones. Calcium is a main ingredient for bone building, notes calcium and osteoporosis expert Robert Heaney, MD, professor of medicine at Creighton University in Omaha.
"You have to have calcium or you can't store it as bone," Heaney tells WebMD. "The human body is born with 25 grams of calcium at birth. We have to build that up by diet. The question is how much is enough to do that."