The fact that most MAs on results from RCTs did not show a beneficial effect does not disprove the hypothesis suggested by observational findings on adverse health outcomes of low 25OHD levels
Background A large number of observational studies have reported harmful effects of low 25-hydroxyvitamin D ( 25OHD ) levels on non-skeletal outcomes .
We performed a systematic quantitative review on characteristics of r and omized clinical trials ( RCTs ) included in meta-analyses ( MAs ) on non-skeletal effects of vitamin D supplementation .
Vitamin D supplementation and depression in the women's health initiative calcium and vitamin D trial.
While observational studies have suggested that vitamin D deficiency increases risk of depression , few clinical trials have tested whether vitamin D supplementation affects the occurrence of depression symptoms . The authors evaluated the impact of daily supplementation with 400 IU of vitamin D(3 ) combined with 1,000 mg of elemental calcium on measures of depression in a r and omized , double-blinded US trial comprising 36,282 postmenopausal women . The Burnam scale and current use of antidepressant medication were used to assess depressive symptoms at r and omization ( 1995 - 2000 ) . Two years later , women again reported on their antidepressant use , and 2,263 completed a second Burnam scale . After 2 years , women r and omized to receive vitamin D and calcium had an odds ratio for experiencing depressive symptoms ( Burnam score ≥0.06 ) of 1.16 ( 95 % confidence interval : 0.86 , 1.56 ) compared with women in the placebo group . Supplementation was not associated with antidepressant use ( odds ratio = 1.01 , 95 % confidence interval : 0.92 , 1.12 ) or continuous depressive symptom score . Results stratified by  baseline vitamin D and calcium intake , solar irradiance , and other factors were similar . The findings do not support a relation between supplementation with 400 IU/day of vitamin D(3 ) along  with calcium and depression in older women . Additional trials testing higher doses of vitamin D are needed to determine whether this nutrient may help prevent or treat depression
The fact that most MAs on results from RCTs did not show a beneficial effect does not disprove the hypothesis suggested by observational findings on adverse health outcomes of low 25OHD levels
Background A large number of observational studies have reported harmful effects of low 25-hydroxyvitamin D ( 25OHD ) levels on non-skeletal outcomes .
We performed a systematic quantitative review on characteristics of r and omized clinical trials ( RCTs ) included in meta-analyses ( MAs ) on non-skeletal effects of vitamin D supplementation .