Vitamin D and Health

the 600 µg (24,000 IU) vitamin D 3 + 300 µg 25(OH)D 3 group (66.1%; 95% CI, 53.5-76.8%) compared
with the 600 µg (24,000 IU) vitamin D 3 group (47.9%; 95% CI, 35.8-60.3%) (p=0.048).
Cohort studies
6.146 Menant et al. (2012) assessed the relationship between serum 25(OH)D concentration and falls in a
cohort of community dwelling adults (n=463; age, 70-90y) followed for 1 year. Rate of falls was
significantly increased in men with serum 25(OH)D concentration < 50 nmol/L (IRR=1.94; 95% CI, 1.19-
3.15; p=0.008) but not in women.
Genetic studies
6.147 A study in Italian adults (n=259; mean age, 85y; 66% women) reported that the bb genotype of the
Bsm1 VDR gene was associated with a reduced risk of falls compared with the BB genotype (Onder et
al., 2008). A subsequent study examined VDR polymorphism and falls risk in two separate cohorts
(Barr et al., 2010), the Aberdeen Prospective Osteoporosis Screening Study (APOSS; n=3,209; mean
age, 54.3y) and the Osteoporosis and Ultrasound Study (OPUS; n=1970; mean age, 66.9y). An increase
in falls risk with the BB Bsm1 genotype was found in both cohorts. An association was also found
between Bsm1 polymorphism and balance and muscle power measurements. There was no
association between risk of falls and serum 25(OH)D concentration.
Bone health indices
Summary - Adults ≥ 50y
6.148 A systematic review and meta-analysis of 23 intervention trials reported a small benefit of vitamin D
supplementation on femoral neck BMD (weighted mean difference 0.8%; 95% CI, 0.2-1.4) but no effect on BMD
in either the spine or total hip.
6.149 Out of 2 RCTs not included in the systematic review, 1 found beneficial effects of supplementation on total body
BMD and total hip BMD but not at other sites, while the other reported significantly less mean BMD loss at the
hip with vitamin D supplementation.
6.150 One cohort study showed an association between serum 25(OH)D concentration < 50 nmol/L and greater rate of
loss in hip BMD.
Fracture prevention
6.151 Evidence from 3 meta-analyses on vitamin D supplementation and fracture prevention is mixed. One metaanalysis
is supportive of a beneficial effect of vitamin D supplementation in reducing the risk of non-vertebral
and hip fractures. In the 2 other meta-analyses, vitamin D alone had no effect on fracture risk but both metaanalyses
reported a beneficial effect of vitamin D plus calcium on fracture prevention.
6.152 One RCT reported an increased risk of fracture with a single high annual dose of vitamin D
(12,500 µg/500,000 IU).
6.153 Evidence from 5 cohort studies is mixed: 3 studies reported that serum 25(OH)D concentrations < 45, < 50 and
< 71 nmol/L are associated with increased fracture risk at some skeletal sites; 1 study found that a mean serum
25(OH)D concentration > 50 nmol/L is associated with lower fracture risk in white women but a higher fracture
risk in black women; 1 study found no association between serum 25(OH)D concentration and fracture risk.
Muscle strength and function
6.154 Three meta-analyses of RCTs reported a beneficial effect of vitamin D supplementation on muscle strength and
function in adults ≥ 50y with mean baseline serum 25(OH)D concentration of 24-66 nmol/L, < 30 nmol/L and
< 25 nmol/L; however the latter was based on 2 studies in hospitalised patients in Japan and may not be
applicable to the general population in the UK.
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