The vitamin D story – a 2023 update on fractures and falls

Vitamin D is more than just a vitamin – it is a real hormone with great importance for the bone-muscle unit and for many other tissues and biological processes in the human organism. This narrative review is focused on the available evidence for skeletal effects of vitamin D – possible reduction of falls and fractures in elderly people. We follow the natural path of the vitamin D story with the growing interest and hopes followed by some disappointment and then by mere realism. A number of meta-analyses are discussed in an attempt to better describe the available knowledge and the up-to-date consensus on vitamin D. In short, the existing evidence shows a modest effect of vitamin D supplements on fractures and falls, which may be comparable to that of some older antiresorptives. Current consensus statements identified the following subgroups that would benefit most from vitamin D supplements: the elderly, the institutionalized, those with vitamin D insufficiency/deficiency or secondary hyperparathyroidism, those at higher risk of fractures and falls (osteoporosis included). As fractures and falls seem to be dependent from the baseline levels of vitamin D, serum levels should be measured and supplementation should be tailored accordingly (800 – 2000 IU daily). A combination with daily calcium of 600 – 1200 mg is highly recommended to enhance the skeletal effects of vitamin D. The clinician should be aware of the low patients’ adherence with long-term supplements. In conclusion, vitamin D is a cheap and quite effective option to improve bone health with possible beneficial pleiotropic extra-skeletal effects.