Vitamin D does not improve bone health or prevent fractures, finds study
There is ‘little justification’ for prescribing vitamin D to maintain or improve musculoskeletal health and clinical guidelines should be changed to reflect this, a study has suggested.
Vitamin D supplementation does not reduce falls or fracture risk, and also does not improve bone mineral density, a study published in the Lancet Diabetes and Endocrinology concluded.
The study, carried out by researchers from the Universities of Auckland and Aberdeen, was a meta-analysis of 81 clinical trials, including over 53,000 patients, looking at the effects of vitamin D on fracture rates, falls and bone mineral density. Most studies included women aged over 65 with serum vitamin D levels of less than 50nmol/L and taking vitamin D doses of more than 800IU per day.
The analysis found that vitamin D supplementation did not reduce total fractures, hip fractures or falls by 15% - a clinically meaningful threshold. When the researchers reduced the thresholds, they found that vitamin D still did not reduce falls by 7.5% or total fractures by 5%. They also found that bone mineral density did not increase by a clinically significant level in those taking vitamin D.
The authors said in the paper that they believed the results mean that there is ‘no justification’ for further trials of vitamin D on musculoskeletal outcomes as there is no longer any ambiguity about its benefits.
They said in the paper: ‘In summary, vitamin D supplementation did not have meaningful effects on fracture, falls, or bone mineral density, and future trials are unlikely to alter these conclusions. Therefore, there is little justification for the use of vitamin D supplements to maintain or improve musculoskeletal health, and clinical guidelines should reflect these findings.’
They did caveat that vitamin D supplementation was still appropriate for groups at high risk of rare conditions such as rickets and osteomalacia, which can result after prolonged lack of exposure to the sun.
Researchers found earlier this year that there was no strong link between vitamin D levels and adverse pregnancy outcomes such as gestational diabetes, despite the NICE recommendation that GPs should recommend vitamin D supplementation at first contact with pregnant women.