Extra calcium does not cut fracture risk, research shows
Wednesday, 25 May 2011
Consuming extra dietary calcium does not reduce a woman’s risk of fractures or osteoporosis later in life, shows research. The study, published today on bmj.com, found that consumption much in excess of the UK’s recommendation of 700mg calcium a day conferred no additional benefit.
Countries vary greatly in how much calcium they recommend the over-50s should consume to maintain healthy bones, from 700mg in the UK to 1200mg in the US.
Researchers analysed data from a long-term population study in Sweden, to find out how women’s levels of dietary calcium were associated with their later risk of osteoporosis and fractures.
They followed 61,433 women for 19 years, closely monitoring their diet, especially for intake of calcium and dietary and multivitamin supplements. The women’s height, weight, smoking habits, level of physical activity, educational attainment, menopausal status and use of post-menopausal oestrogen therapy were also recorded.
During follow-up, 14,738 women had a first fracture, of whom 3871 had first hip fractures. Osteoporosis was diagnosed in 20% of the 5022 women who were randomly selected to have dual energy x ray absorptiometry.
The lowest fracture risk occurred in women who consumed about 750mg calcium daily – above that amount, there was no further decrease in risk. In fact there was an association between high calcium intake and an increased rate of hip fracture, although the authors warn that this result must be interpreted with caution.
They conclude: “Dietary calcium intakes below approximately 700mg per day in women were associated with an increased risk of hip fracture, any fracture, and of osteoporosis.
“The highest reported calcium intake did not further reduce the risk of fractures of any type, or of osteoporosis, but was associated with a higher rate of hip fracture.”
“Our observational data suggest that in the prevention of osteoporotic fractures emphasis should be placed on individuals with a low intake of calcium rather than increasing the intake of those already consuming satisfactory amounts.”