There is little point in recommending vitamin D supplements to improve bone health and prevent fractures and falls in elderly patients, according to the largest analysis of research evidence to date.
Vitamin D supplements have long been recommended for older people to treat or prevent osteoporosis.
“Vitamin D does not prevent fractures, falls or improve bone mineral density”
However, the major review of more than 80 trials, published in the Lancet Diabetes and Endocrinology journal, concluded it made virtually no difference, prompting calls for clinical guidance to be changed.
Researchers from the University of Auckland, New Zealand and University of Aberdeen, Scotland examined the findings of 81 randomised trials in all – most looking at the impact of taking vitamin D on its own.
They found taking the supplements did not improve bone mineral density in adults or prevent fractures or falls.
The study also found no difference in effect when it came to taking a higher dose of vitamin D versus a lower dose.
There was therefore little justification in using vitamin D to maintain or improve musculoskeletal health with the exception of the rare occasions it was needed to prevent rickets or osteomalacia –softening of the bones – in high risk individuals, concluded the authors.
“Since the last major review of evidence in 2014, more than 30 randomised controlled trials on vitamin D and bone health have been published, nearly doubling the evidence base available,” said lead author Mark Bolland, associate professor at the University of Auckland.
“Our meta-analysis finds that vitamin D does not prevent fractures, falls or improve bone mineral density, whether at high or low dose,” he said. “Clinical guidelines should be changed to reflect these findings.
There was also little point in doing further research on the impact of vitamin D on bone health, he added.
“On the strength of existing evidence, we believe there is little justification for more trials of vitamin D supplements looking at musculoskeletal outcomes,” he said.
However, the fact only a small percentage of trials looked at the impact of taking supplements on people with an actual vitamin D deficiency meant more research might be needed for this particular group.
“I look forward to those studies giving us the last word on vitamin D”
The findings from the research review were likely to prove unpalatable to many patients – and clinicians – who remained convinced that taking vitamin D was beneficial, according to one expert commentator.
“The context for this analysis lies in the fact many patients (and doctors) have been persuaded by various studies and social media that vitamin D is a cure-all,” said Professor John Chris Gallagher from the Creighton University Medical Centre in Omaha, US, writing in a linked article in the same journal.
Many “fervent supporters” would point to the wider benefits of taking vitamin D beyond bone health, he suggested.
But he pointed out research was under way that could provide clear evidence of whether vitamin D supplements made any difference full stop.
“Within three years, we might have that answer because there are approximately 100,000 patients currently enrolled in randomised, placebo-controlled trials of vitamin D supplementation,” he said.
He added: “I look forward to those studies giving us the last word on vitamin D.”