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Got It, Hide thisBolland MJ, Leung W, Tai V, et al. Calcium intake and risk of fracture: systematic review. BMJ. 2015 Sep 29;351:h4580.
In people over 50 years of age, does increasing calcium in the diet or with supplements affect risk of fractures? See related Evidence Summary of a review by Tai.
Calcium is important for bone health, but people often don’t get enough in the food they eat. As we age, we lose bone mass (osteopenia or osteoporosis) and have greater risk of fractures (broken bones). Doctors often recommend eating more calcium-rich foods or taking calcium supplements to reduce fractures.
The researchers did a systematic review, including studies up to September 2014. They found 26 randomized controlled trials of calcium supplements that included 69 107 people.
The main results were total number of fractures and fractures at the hip, vertebrae (bones of the spinal column), and forearm.
Calcium supplements could be combined with other treatments such as vitamin D as long as both groups received the other treatment.
3 trials had a low risk of bias; the rest had a higher risk of bias.
Calcium supplements reduced total fractures and vertebral fractures by a small amount but did not affect hip or forearm fractures.
When only studies with low risk of bias were analyzed, there were no differences in fractures between calcium and no calcium groups.
In people over 50 years of age, calcium supplements reduce risk of total and vertebral fractures by a small amount and do not reduce hip or forearm fractures.
Outcomes | Number of trials (number of people) | Rate of events with calcium | Rate of events without calcium | Effect of calcium at 1 to 7 years |
All fractures | 23 trials (58,573 people) | 11% | 12% | About 1 less person out of 100 had a fracture |
Hip fractures | 16 trials (56,648 people) | 1.7% | 1.8% | No difference in hip fractures* |
Vertebral fractures | 15 trials (48,967 people) | 1.3% | 1.5% | About 2 fewer people out of 1000 had vertebral fractures |
Forearm fractures | 10 trials (51,775 people) | 2.8% | 2.9% | No difference in forearm fractures* |