Calcium and/or Vitamin D Supplementation for the Prevention of Fragility Fractures: Who Needs It?

Nutrients. 2020 Apr 7;12(4):1011. doi: 10.3390/nu12041011.


Vitamin D and calcium have different biological functions, so the need for supplementation, and its safety and efficacy, need to be evaluated for each separately. Vitamin D deficiency is usually the result of low sunlight exposure (e.g., in frail older people, those who are veiled, those with dark-skin living at higher latitudes) and is reversible with calciferol 400-800 IU/day. Calcium supplements produce a 1% increase in bone density in the first year of use, without further increases subsequently. Vitamin D supplements do not improve bone density in clinical trials except in analyses of subgroups with baseline levels of 25-hydroxyvitamin D <30 nmol/L. Supplementation with calcium, vitamin D, or their combination does not prevent fractures in community-dwelling adults, but a large study in vitamin D-deficient nursing home residents did demonstrate fracture prevention. When treating osteoporosis, co-administration of calcium with anti-resorptive drugs has not been shown to impact on treatment efficacy. Correction of severe vitamin D deficiency (<25 nmol/L) is necessary before use of potent anti-resorptive drugs to avoid hypocalcemia. Calcium supplements cause gastrointestinal side effects, particularly constipation, and increase the risk of kidney stones and, probably, heart attacks by about 20%. Low-dose vitamin D is safe, but doses >4000 IU/day have been associated with more falls and fractures. Current evidence does not support use of either calcium or vitamin D supplements in healthy community-dwelling adults.

Keywords: bisphosphonate; calcium; osteoporosis; vitamin D.

Publication types

  • Review

MeSH terms

  • Adult
  • Aged
  • Bone Density / drug effects
  • Calcium / deficiency*
  • Calcium, Dietary / therapeutic use*
  • Female
  • Fractures, Bone* / etiology
  • Fractures, Bone* / metabolism
  • Fractures, Bone* / pathology
  • Fractures, Bone* / prevention & control
  • Humans
  • Male
  • Vitamin D / analogs & derivatives*
  • Vitamin D / metabolism
  • Vitamin D / therapeutic use
  • Vitamin D Deficiency / complications
  • Vitamin D Deficiency / metabolism
  • Vitamin D Deficiency / pathology
  • Vitamin D Deficiency / prevention & control*


  • Calcium, Dietary
  • Vitamin D
  • 25-hydroxyvitamin D
  • Calcium