By Nicholas Bakalar
One analysis reviewed 59 randomized controlled trials of the effect of dietary and supplemental calcium on bone density. Together, the trials included 13,790 men and women over 50. The data showed that more calcium in the diet or taken as supplements increased bone density about 1 percent to 2 percent — too little to have any effect on fractures.
The other review pooled the results of 55 studies of calcium intake and fractures and found no significant association of overall calcium intake with broken bones. Some studies of supplements showed a slightly reduced risk for vertebral fracture, but none for hip or forearm fractures. The four most rigorous, randomized controlled trials of calcium supplements included more than 45,000 participants and showed no association between supplements and the risk of fracture at any site.
“We found no evidence that calcium intake is associated with the risk for fracture,” said the senior author, Dr. Mark J. Bolland, an associate professor of medicine at the University of Auckland in New Zealand, “so if you have a normal diet, you don’t need to worry about your calcium intake.”