Please note this release is under embargo.
Embargo to 11.30am Wednesday 30th September (NZ Time) BMJ
Calcium supplement no help for bones
University of Auckland - Media Release - 28 September 2015
Embargo to 11.30am Wednesday 30th September (NZ Time) BMJ
Calcium supplements no help for bones
Increasing calcium intake through diet or supplements should not be recommended for fracture or osteoporosis prevention,
according to University of Auckland Associate Professor of Medicine, Dr Mark Bolland.
Two studies published in The British Medical Journal this week, conclude that increasing calcium intake is unlikely to improve bone health or prevent fractures in older
people.
“Collectively, these results suggest that Clinicians, advocacy organisations and health policymakers should not
recommend increasing calcium intake for fracture prevention, either by use of calcium supplements or dietary sources,”
says Dr Bolland. “For most patients who are concerned about their bone health, they do not need to worry about their
calcium intake.”
Guidelines advise older men and women to take at least 1000-1200 mg/day of calcium to improve bone density and prevent
fractures, and many people take calcium supplements to meet these recommendations.
Recent concerns about the safety of calcium supplements have led experts to recommend increasing calcium intake through
food rather than by taking supplements, but the effect on bone health was unknown.
A team of researchers, led by Dr Bolland, set out to examine the evidence underpinning recommendations to increase
calcium intake from dietary sources or supplements to improve bone health and prevent fractures.
They analysed the available evidence from randomised controlled trials and observational studies of extra dietary or
supplemental calcium in women and men aged over 50. Study design and quality were taken into account to minimise bias.
“In the first study, we found that increasing calcium intake from dietary sources or by taking supplements produces
small (one to two percent) increases in bone mineral density, which are unlikely to lead to a clinically meaningful
reduction in risk of fracture”, says Dr Bolland.
“The second study found that dietary calcium intake is not associated with risk of fracture, and there is no clinical
trial evidence that increasing calcium intake from dietary sources prevents fractures,” he says.
“It is time to revisit recommendations to increase calcium intake beyond a normal balanced diet,” says co-author,
Professor Karl Michaëlsson from Uppsala University in Sweden, in an accompanying editorial.
He says that ever increasing intakes of calcium and vitamin D recommended by some guidelines defines virtually the whole
population aged over 50 at risk.
“Yet most will not benefit from increasing their intakes”, he says, “and will be exposed instead to a higher risk of
adverse events [such as gastrointestinal side effects]”.
“The weight of evidence against such mass medication of older people is now compelling, and it is surely time to
reconsider these controversial recommendations,” he says.
ENDS
Notes to Editors
• Research: Calcium intake and risk of fracture: systematic review
• Research: Calcium intake and bone mineral density: systematic review and meta-analysis
• Editorial: Calcium supplements do not prevent fractures
Journal title: The British Medical Journal (BMJ)
• link to study 1: http://www.bmj.com/cgi/doi/10.1136/bmj.h4580
• link to study 2: http://www.bmj.com/cgi/doi/10.1136/bmj.h4183
• link to editorial: http://www.bmj.com/cgi/doi/10.1136/bmj.h4825