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 supplements in pregnant Asian women: effects on calcium status and fetal growth.
In a double-blind trial of vitamin D supplements in pregnant Asian women calciferol ( ergocalciferol , 1000 IU/day ) was administered to 59 women and placebo to 67 controls during the last trimester . The two groups had similar distributions of maternal age , height , parity , number of vegetarians , countries of origin , and sex and gestation of the infants . At entry to the trial maternal serum 25-hydroxy vitamin D ( 25-OHD ) concentrations were low in both treatment and control groups and significantly lower in vegetarians than non-vegetarians . Mothers in the treatment group gained weight faster in the last trimester than those in the control group , and at term they and their infants all had adequate plasma 25-OHD concentrations , Mothers and infants in the control group , however , had low plasma concentrations of 25-OHD and calcium and raised plasma alkaline phosphatase ( bone isoenzyme ) activity . Five of these infants developed symptomatic hypocalcaemia . Almost twice as many infants in the control group were small for gestational age ( 29 % v 15 % ) , but there were no significant differences between the two groups of infants in antropometric measurements . Infants in the control group , however , had larger fontanelles , suggesting impaired ossification of the skull . Because of the benefits to mothers and infants in the treatment group and the absence of side effects , vitamin D supplements should be given to all pregnant Asian women in the United Kingdom
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 .