• Assessment
    What is the evidence regarding the effect of supplemental vitamin D on bone density in post-menopausal women and older adult men?
    • Conclusion

      One meta-analysis (a systematic review of 19 studies), five RCTs and two cross-sectional studies found an association between supplemental vitamin D and bone mineral density (BMD) in post-menopausal women and older adult men. Vitamin D dosage ranged from 400 IU to 1,400 IU (10mcg to 35 mcg) per day, however it is difficult to determine the optimal dosage and the effect of vitamin D alone, since varying combinations of nutrients were used including calcium and vitamin K. One additional RCT with a supplement containing 200 IU (five mcg) of Vitamin D and other nutrients found an improvement in bone turnover markers, but no effect in bone mineral density. Further research is needed to determine the independent association between supplemental vitamin D and bone mineral density in post-menopausal women and older adult men.

    • Grade: II
      • Grade I means there is Good/Strong evidence supporting the statement;
      • Grade II is Fair;
      • Grade III is Limited/Weak;
      • Grade IV is Expert Opinion Only;
      • Grade V is Not Assignable.
      • High (A) means we are very confident that the true effect lies close to that of the estimate of the effect;
      • Moderate (B) means we are moderately confident in the effect estimate;
      • Low (C) means our confidence in the effect estimate is limited;
      • Very Low (D) means we have very little confidence in the effect estimate.
      • Ungraded means a grade is not assignable.
    What is the evidence regarding the effect of supplemental Vitamin D on fractures in post-menopausal women and older adult men?
    • Conclusion

      One meta-analysis/systematic review, combining the results of 13 RCTs suggest that supplementation with vitamin D3 (400 IU to 800 IU) plus calcium (500mg to 1,200mg) may be beneficial in reducing the incidence of fractures in institutionalized older adults. The reduction of fractures might be accounted for by higher mean serum levels of 25(OH)D (at least 74nmol per L), due to good volunteer compliance. One RCT concluded that supplementation with 100,000 IU vitamin D2 every four months, does not significantly reduce fractures in institutionalized older adults. Further research is needed to determine the role of vitamin D3 and vitamin D2 supplementation alone in reducing the incidence of fractures.

    • Grade: II
      • Grade I means there is Good/Strong evidence supporting the statement;
      • Grade II is Fair;
      • Grade III is Limited/Weak;
      • Grade IV is Expert Opinion Only;
      • Grade V is Not Assignable.
      • High (A) means we are very confident that the true effect lies close to that of the estimate of the effect;
      • Moderate (B) means we are moderately confident in the effect estimate;
      • Low (C) means our confidence in the effect estimate is limited;
      • Very Low (D) means we have very little confidence in the effect estimate.
      • Ungraded means a grade is not assignable.
    What is the evidence regarding the effect of supplemental vitamin D on falls in post-menopausal women and older adult men?
    • Conclusion

      One meta-analysis/systematic review, one RCT and one prospective cohort study found that evidence is inconsistent regarding the effect of supplemental vitamin D2 or vitamin D3 on the reduction of falls in older adult men and women. Further research is needed to determine the role of vitamin D2 or vitamin D3 alone in preventing falls in older adults.

    • Grade: III
      • Grade I means there is Good/Strong evidence supporting the statement;
      • Grade II is Fair;
      • Grade III is Limited/Weak;
      • Grade IV is Expert Opinion Only;
      • Grade V is Not Assignable.
      • High (A) means we are very confident that the true effect lies close to that of the estimate of the effect;
      • Moderate (B) means we are moderately confident in the effect estimate;
      • Low (C) means our confidence in the effect estimate is limited;
      • Very Low (D) means we have very little confidence in the effect estimate.
      • Ungraded means a grade is not assignable.
    Are specific circulating concentrations of 25 hydroxyvitamin D [25(OH)D] associated with bone health outcomes in post-menopausal women and older adult men?
    • Conclusion

      Two RCTs and one meta-analysis (a systematic review of 42 papers) found that evidence is inconclusive regarding the association of specific circulating concentrations of 25-hydroxyvitamin D [25(OH)D] and bone health outcomes in post-menopausal women and older adult men. In those studies reporting a positive association in the meta-analysis, specific 25(OH)D concentrations ranging from 40nmol to 80nmol per L were shown to have declines in bone health outcomes (fractures, falls and bone loss). Further research is needed to determine the association of specific circulating concentrations of 25(OH)D with bone health outcomes.

    • Grade: III
      • Grade I means there is Good/Strong evidence supporting the statement;
      • Grade II is Fair;
      • Grade III is Limited/Weak;
      • Grade IV is Expert Opinion Only;
      • Grade V is Not Assignable.
      • High (A) means we are very confident that the true effect lies close to that of the estimate of the effect;
      • Moderate (B) means we are moderately confident in the effect estimate;
      • Low (C) means our confidence in the effect estimate is limited;
      • Very Low (D) means we have very little confidence in the effect estimate.
      • Ungraded means a grade is not assignable.
    What is the effect of vitamin D supplementation on circulating 25(OH)D in post-menopausal women and older adult men?
    • Conclusion

      Two RCTs and one meta-analysis (systematic review of 44 RCTs) found a direct effect of oral vitamin D3 supplementation on circulating levels of 25(OH)D in post-menopausal women and older adult men. In studies reporting a treatment effect, specific doses ranging from five mcg to 50mcg (200 IU to 2,000 IU) of vitamin D3 were utilized. Meta-regression results suggested that 100 IU (2.5mcg) of vitamin D3 will increase the serum 25(OH)D concentrations by one nmol to two nmol per L suggesting doses of 400 IU to 800 IU (10mcg to 20mcg) daily may be inadequate to prevent vitamin D deficiency in at-risk individuals. It is difficult to determine adequate intake since there is a lack of agreement regarding optimal levels of serum 25(OH)D. Additional research is needed to determine the vitamin D dosage necessary to reach optimal serum 25(OH)D levels in post-menopausal women and older adult men.

    • Grade: II
      • Grade I means there is Good/Strong evidence supporting the statement;
      • Grade II is Fair;
      • Grade III is Limited/Weak;
      • Grade IV is Expert Opinion Only;
      • Grade V is Not Assignable.
      • High (A) means we are very confident that the true effect lies close to that of the estimate of the effect;
      • Moderate (B) means we are moderately confident in the effect estimate;
      • Low (C) means our confidence in the effect estimate is limited;
      • Very Low (D) means we have very little confidence in the effect estimate.
      • Ungraded means a grade is not assignable.