Millions of older adults take calcium and vitamin D supplements every day expecting to protect their bones. A sweeping new review suggests those expectations may not be supported by the evidence.
The review, published in The BMJ and reported by Science Daily, analyzed data from 69 randomized controlled trials involving 153,902 adults. Researchers in Canada compared calcium supplements, vitamin D supplements, and a combination of both against placebo or no treatment. They looked for meaningful reductions in fractures and falls. They did not find them.
The findings showed little to no reduction in overall fracture risk from calcium supplements alone, based on moderate certainty evidence drawn from 11 trials covering 9,067 participants. For vitamin D supplements, high certainty evidence from 36 trials involving 92,045 participants showed the same result. Combined supplementation, drawn from 15 trials with 51,126 participants, also showed little to no benefit at high certainty.
The researchers also looked at specific types of fractures, including hip fractures, which are among the most serious injuries older adults face. Again, the evidence showed little to no protective effect. Fall prevention showed similar results.
Falls are a serious public health concern for older adults. Nearly one in three people age 65 and older experiences a fall each year, and many result in fractures. Those fractures can cause pain, reduce independence, lower quality of life, and in some cases lead to long-term residential care.
Previous reviews had already raised questions about these supplements. Research had generally found no reduction in fracture risk from either supplement alone, while results for the two taken together had been mixed. The role of vitamin D in fall prevention had also remained uncertain. Even so, vitamin D supplements continued to be widely recommended by healthcare providers, professional guidelines, and regulatory agencies. Prescriptions for these supplements had risen considerably in recent years.
The researchers assessed each study using established methods to evaluate potential bias and the certainty of the evidence. The quality of the trials varied, but the overall picture remained consistent across the analysis.
