All you need to read in the other general journalsBMJ 2012; 344 doi: https://doi.org/10.1136/bmj.d8345 (Published 04 January 2012) Cite this as: BMJ 2012;344:d8345
Who needs vitamin D?
Vitamin D comprises an enigmatic collection of steroid hormones and is best known for helping to regulate bone mineralisation through calcium and phosphate metabolism. Deficiency, although poorly defined, is thought to be widespread worldwide and has been linked to heart disease, cancers, diabetes, and cognitive impairment, as well as poor bone health. Whether supplements can prevent any disease outside the skeleton remains an open question, however, and two recent reviews conclude that yet more research is needed—preferably the prospective randomised variety⇑.
The first review focused on cancers and fractures. Combined supplements of vitamin D and calcium reduced fracture risk for older adults in 16 trials (pooled relative risk 0.88, 95% CI 0.78 to 0.99), but the benefit was confined to those living in institutions. Analysis of 28 observational studies failed to find a consistent association between serum concentrations of vitamin …