The ongoing D-lemma of vitamin D supplementation for nonskeletal health and bone health

Curr Opin Endocrinol Diabetes Obes. 2019 Dec;26(6):301-305. doi: 10.1097/MED.0000000000000508.


Purpose of review: The goal of this review is to give some perspective on the results and conclusions of three recent randomized controlled vitamin D intervention studies that have challenged the health benefit of vitamin D supplementation for reducing risk for cardiovascular disease, cancer, all-cause mortality and type 2 diabetes and improving bone health.

Recent findings: Vitamin D supplementation to adults who were vitamin D sufficient or insufficient did not reduce risk for developing cardiovascular disease, cancer, type 2 diabetes nor increases bone mineral density (BMD). Patients who were vitamin D deficient with cancer and received vitamin D reduced risk for mortality by 25% and prediabetic adults who were vitamin D deficient and received vitamin D reduced their risk of developing type 2 diabetes by 62%. Older adults receiving 4000 and 10 000 IUs of vitamin D3 daily for 3 years had reduced radial BMD but had no change in either total hip areal bone density or bone strength in the radius and tibia.

Summary: Caution is needed when evaluating results and conclusions from randomized controlled trials that investigate health benefits of vitamin D; most studies suggest health benefits when vitamin D supplementation is provided to vitamin D deficient populations and little benefit when given to populations that are vitamin D sufficient/insufficient.

Publication types

  • Review

MeSH terms

  • Adult
  • Aged
  • Bone Density / drug effects*
  • Bone and Bones / drug effects
  • Bone and Bones / physiology
  • Diabetes Mellitus, Type 2 / prevention & control
  • Dietary Supplements* / adverse effects
  • Humans
  • Mortality
  • Neoplasms / blood
  • Neoplasms / drug therapy
  • Neoplasms / mortality
  • Prediabetic State / blood
  • Prediabetic State / complications
  • Prediabetic State / drug therapy
  • Risk Factors
  • Vitamin D / administration & dosage*
  • Vitamin D / adverse effects
  • Vitamin D Deficiency / blood
  • Vitamin D Deficiency / complications
  • Vitamin D Deficiency / drug therapy*


  • Vitamin D