Evidence Summary

What is an Evidence Summary?

Key messages from scientific research that's ready to be acted on

Got It, Hide this
  • Rating:

In people over 50 years of age, calcium supplements have a small effect on preventing fractures

Bolland MJ, Leung W, Tai V, et al. Calcium intake and risk of fracture: systematic review. BMJ. 2015 Sep 29;351:h4580.

Review question

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.

How the review was done

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.

What the researchers found

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.

Calcium supplements vs no calcium supplements in people over 50 years of age


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)



About 1 less person out of 100 had a fracture

Hip fractures

16 trials (56,648 people)



No difference in hip fractures*

Vertebral fractures

15 trials (48,967 people)



About 2 fewer people out of 1000 had vertebral fractures

Forearm fractures

10 trials (51,775 people)



No difference in forearm fractures*

*Although the rates for the 2 groups look different, the differences were not statistically significant. This means that the difference could simply be due to chance rather than due to different treatments.


Randomized controlled trials
Studies where people are assigned to one of the treatments purely by chance.
Risk of bias
Possibility of some systematic error in the studies.
Systematic review
A comprehensive evaluation of the available research evidence on a particular topic.

Related Web Resources

  • Patient education: Quitting smoking (Beyond the Basics)

    UpToDate - patient information
    There are many strategies available to help you quit smoking. Start by picking a quit date. Consider speaking with a health care provider for advice, seeking in-person or telephone support, making behavioural changes, and using different medications such as varenicline, bupropion, or nicotine replacement therapy.
  • Worried about dementia? Here are 5 ways to cut your risk

    Dementia affects millions of people around the world, and there is no current treatment. There are a few ways to lower your risk. Eat a well-balanced diet, exercise, stay social, and limit alcohol and smoking.
  • Heartburn and GERD

    Informed Health Online
    Regular acid reflux may mean you have gastro-esophageal reflux disease, also known as GERD. Treatment for GERD includes lifestyle changes, medication or surgery.
DISCLAIMER These summaries are provided for informational purposes only. They are not a substitute for advice from your own health care professional. The summaries may be reproduced for not-for-profit educational purposes only. Any other uses must be approved by the McMaster Optimal Aging Portal (

Register for free access to all Professional content