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 .
The Effect of the Systemic Inflammatory Response on Plasma Vitamin 25 (OH) D Concentrations Adjusted for Albumin
Background Plasma 25-hydroxyvitamin D ( 25(OH ) D ) deficiencies are associated with several diseases . The magnitude of systemic inflammatory response , as evidence d by C-reactive protein ( CRP ) , is a major factor associated with lower 25(OH)D. Other aspects of the systemic inflammatory response may be important in determining plasma 25 (OH)D concentrations . Aim To examine the relationship between plasma 25(OH)D , CRP and albumin concentrations in two patient cohorts . Methods 5327 patients referred for nutritional assessment and 117 patients with critical illness were examined .  Plasma 25 ( OH ) D concentrations were measured using st and ard methods . Intra and between assay imprecision was < 10 % . Result In the large cohort , plasma 25 ( OH ) D was significantly associated with CRP ( r s = −0.113 , p<0.001 ) and albumin ( r s = 0.192 , p<0.001 ) . 3711 patients had CRP concentrations ≤10 mg/L ; with decreasing albumin concentrations ≥35 , 25–34 and < 25 g/l , median concentrations of 25 ( OH ) D were significantly lower from 35 to 28 to 14 nmol/l ( p<0.001 ) . This decrease was significant when albumin concentrations were reduced between 25–34 g/L ( p<0.001 ) and when albumin < 25 g/L ( p<0.001 ) . 1271 patients had CRP concentrations between 11–80 mg/L ; with decreasing albumin concentrations ≥35 , 25–34 and < 25 g/l , median concentrations of 25 ( OH ) D were significantly lower from 31 to 24 to 19 nmol/l ( p<0.001 ) . This decrease was significant when albumin concentration were 25–34 g/L ( p<0.001 ) and when albumin < 25 g/L ( p<0.001 ) . 345 patients had CRP concentrations > 80 mg/L ; with decreasing albumin concentrations ≥35 , 25–34 and < 25 g/l , median concentrations of 25 ( OH ) D were not significantly altered varying from 19 to 23 to 23 nmol/l . Similar relationships were also obtained in the cohort of patients with critical illness . Conclusion Plasma concentrations of 25(OH ) D were independently associated with both CRP and albumin and consistent with the systemic inflammatory response as a major confounding factor in determining vitamin D status
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 .