Vitamin D and Health

Bone health indices beyond rickets and osteomalacia
6.165 Bone health indices (BMC/BMD/biochemical markers of bone formation and resorption) were
considered in all life stage groups. Findings from studies that considered the effect of vitamin D
supplementation on bone health indices or associations between serum 25(OH)D concentration and
bone health indices varied by life stage. Evidence was suggestive of a positive association between
maternal 25(OH)D concentration during pregnancy and bone health indices in the fetus/newborn,
however the physiological significance of this is not known. Evidence was also suggestive of beneficial
effects of vitamin D supplementation on bone health indices at some skeletal sites in adults aged
≥ 50y. Effects of vitamin D supplementation on bone health indices of infants, children and
adolescents is inconsistent but the majority of RCTs did not find any effect. The evidence base for
children aged 1-3y and adults aged < 50y was too small to draw any conclusions.
Fracture prevention
6.166 Data on vitamin D supplementation and fracture prevention in adults aged ≥ 50y are mixed but
suggest that vitamin D plus calcium is more effective in reducing fracture risk than vitamin D alone.
On balance, vitamin D supplements had no beneficial effect on fracture risk in adults aged ≥ 50y.
6.167 Evidence on the effect of vitamin D supplementation or serum 25(OH)D concentration and stress
fracture risk in younger age groups is insufficient to draw firm conclusions.
Muscle strength and function
6.168 Limited evidence suggests a beneficial effect of vitamin D supplementation on muscle function in
adolescent girls with a mean serum 25(OH)D concentration < 18 nmol/L and in adults aged < 50y with
a mean serum 25(OH)D concentration < 30 nmol/L.
6.169 In adults aged ≥ 50y, evidence is mixed but, overall, was suggestive of a beneficial effect of vitamin D
supplementation on muscle strength and function at mean baseline serum 25(OH)D concentrations
ranging between < 25 and 66 nmol/L. Evidence from cohort studies was also supportive of an
association between mean serum 25(OH)D concentration and muscle strength and function when
baseline serum 25(OH)D concentration is < 50 nmol/L.
Falls
6.170 Evidence on vitamin D and falls is mixed but, overall, was suggestive of a beneficial effect of vitamin D
supplementation in reducing fall risk in adults ≥ 50y with mean baseline serum 25(OH)D
concentrations ranging between < 25 and around 80 nmol/L.
6.171 Two RCTs reported that high-dose vitamin D supplementation increased fall risk. The
supplementation dose was administered annually in 1 RCT (12,500 µg/500,000 IU) and monthly in the
other (1500 µg/60,000 IU or 600 µg/24,000 IU vitamin D 3 + 300 µg 25(OH)D 3 ). Serum 25(OH)D
concentrations achieved in these studies ranged from 75 to 90 nmol/L. High doses of vitamin D,
administered annually or monthly, may have different effects from daily supplementation at lower
doses.
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