Recent meta-analyses reinforce the finding that 10 - 20 μg per day of vitamin D can reduce all-cause mortality and cancer mortality in middle-aged and older people .
Although vitamin D doses were greater than those assessed in the past , we found no new evidence that supplementation could have an effect on most non-skeletal conditions , including cardiovascular disease , adiposity , glucose metabolism , mood disorders , muscular function , tuberculosis , and colorectal adenomas , or on maternal and perinatal conditions .
The compilation of results from 83 trials showed that vitamin D supplementation had no significant effect on biomarkers of systemic inflammation .
The main new finding highlighted by this systematic review is that vitamin D supplementation might help to prevent common upper respiratory tract infections and asthma exacerbations .
There remains little evidence to suggest that vitamin D supplementation has an effect on most conditions , including chronic inflammation , despite use of increased doses of vitamin D , strengthening the hypothesis that low vitamin D status is a consequence of ill health , rather than its cause .
We further hypothesise that vitamin D supplementation could exert immunomodulatory effects that strengthen resistance to acute infections , which would reduce the risk of death in debilitated individuals .
Prevention of urinary tract infections with vitamin D supplementation 20,000 IU per week for five years. Results from an RCT including 511 subjects
Abstract Background : In observational studies vitamin D deficiency is associated with increased risk of infections , whereas the effect of vitamin D supplementation in r and omized controlled trials is non-conclusive . Methods : Five hundred and eleven subjects with prediabetes were r and omized to vitamin D3 ( 20,000 IU per week ) versus placebo for five years . Every sixth month , a question naire on respiratory tract infections ( RTI ) ( common cold , bronchitis , influenza ) and urinary tract infection ( UTI ) was filled in . Results : Mean baseline serum 25-hydroxyvitamin D ( 25(OH)D ) level was 60 nmol/L. Two hundred and fifty-six subjects received vitamin D and 255 placebo . One hundred and sixteen subjects in the vitamin D and 111 in the placebo  group completed the five-year study . Eighteen subjects in the vitamin D group and 34 subjects in the placebo group reported UTI during the study ( p < 0.02 ) , whereas no significant differences were seen for RTI . The effect on UTI was most pronounced in males . The effect of vitamin D on UTI was unrelated to baseline serum 25(OH)D level . Conclusion : Supplementation with vitamin D might prevent UTI , but confirmatory studies are needed
Recent meta-analyses reinforce the finding that 10 - 20 μg per day of vitamin D can reduce all-cause mortality and cancer mortality in middle-aged and older people .
Although vitamin D doses were greater than those assessed in the past , we found no new evidence that supplementation could have an effect on most non-skeletal conditions , including cardiovascular disease , adiposity , glucose metabolism , mood disorders , muscular function , tuberculosis , and colorectal adenomas , or on maternal and perinatal conditions .
The compilation of results from 83 trials showed that vitamin D supplementation had no significant effect on biomarkers of systemic inflammation .
The main new finding highlighted by this systematic review is that vitamin D supplementation might help to prevent common upper respiratory tract infections and asthma exacerbations .
There remains little evidence to suggest that vitamin D supplementation has an effect on most conditions , including chronic inflammation , despite use of increased doses of vitamin D , strengthening the hypothesis that low vitamin D status is a consequence of ill health , rather than its cause .
We further hypothesise that vitamin D supplementation could exert immunomodulatory effects that strengthen resistance to acute infections , which would reduce the risk of death in debilitated individuals .