Australian researchers say children who take calcium supplements will have only small improvements in bone density, which are unlikely to reduce the risk of fractures later.
"Our results provide only limited support for the use of calcium supplementation in healthy children as a public health intervention," write researcher Tania Winzenberg, of Menzies Research Institute in Hobart, Australia, and colleagues.
Instead, they say other approaches, such as increasing vitamin D intake and eating more fruits and vegetables, may be a better strategy for building strong bones.
Researchers say that osteoporosis is a major public health issue, particularly among women, and at least 90% of the maximum bone mass a person will ever attain is obtained by age 18. Therefore, finding ways to maximize bone mass during childhood through diet and physical activity to reduce the risk of broken bones and osteoporosis later in life is a hot topic.
Calcium Supplements for Kids Limited
In the study, published in the journal BMJ, researchers analyzed 19 studies on calcium supplementation and bone health involving more than 2,800 children.
There are several limitations to this study. Children who have medical problems or are taking drugs that can affect bone metabolism were not included in the studies that were reviewed. Also, very few of the children in the studies had low baseline intake of calcium to start with. The researchers also didn't look at actual occurrence of fractures.
The results showed that calcium supplementation had no effect on bone mineral density (a measure of bone strength) in areas at greater risk for fracture later in life, such as the hip and lumbar spine.
In addition, there was only a small improvement in bone density in the upper limbs (arms). Children taking the calcium supplements had only 1.7% better bone density in their upper limbs than children who didn't take the supplements.
"The small effect of calcium supplementation on bone mineral density in the upper limb is unlikely to reduce the risk of fracture, either in childhood or later life, to a degree of major public health importance," write the researchers. "It may be appropriate to explore alternative nutritional interventions, such as increasing vitamin D concentrations and intake of fruit and vegetables."
SOURCES: Winzenberg, T. BMJ, Sept. 15 online first edition. News release, British Medical Journals.
By Jennifer Warner
Reviewed by Louise Chang