Vitamin A vs placebo
Change in vitamin A concentrations (µmol/L) · adults with HIV infection
1 finding from 1 review
- no estimate extracted3 studies · 495 participantsLow
Findings
What do systematic reviews say?
1,126 questions · 1,225 findings · 111 reviews
No studies found 235 · 19.2%GRADE not reported 260 · 21.2%Very low 207 · 16.9%Low 271 · 22.1%Moderate 177 · 14.4%High 75 · 6.1%
Vitamin A vs placebo or usual care
Vitamin A deficiency · children aged between 6 months and 5 years
Vitamin A supplementation probably leads to lower vitamin A deficiency compared with placebo or usual care (moderate certainty).
1 finding from 1 review
- Vitamin A supplementation for preventing morbidity and mortality in children from six months to five years of age 2022 · Cochrane Headline outcomes onlyRR 0.71 [0.65, 0.78]4 studies · 2262 participantsModerate
Vitamin A plus iron plus folate vs iron plus folate
Total fetal loss (including miscarriages or combined miscarriages and stillbirths) · pregnant women
Vitamin A plus iron plus folate showed no clear difference in total fetal loss (including miscarriages or combined miscarriages… compared with iron plus folate (low certainty).
1 finding from 1 review
- RR 1.01 [0.61, 1.66]3 studies · 1640 participantsLow
Vitamin A plus iron plus folate vs iron plus folate
Early or late miscarriage · pregnant women
Vitamin A plus iron plus folate showed no clear difference in early or late miscarriage ‐ Vitamin A + iron + folate versus iron +… compared with iron plus folate (low certainty).
1 finding from 1 review
- RR 0.86 [0.46, 1.62]2 studies · 1397 participantsLow
Vitamin A plus iron plus folate vs iron plus folate
Stillbirth ‐ Vitamin A + iron + folate versus iron + folate · pregnant women
Vitamin A plus iron plus folate showed no clear difference in stillbirth ‐ Vitamin A + iron + folate versus iron + folate compared with iron plus folate (low certainty).
1 finding from 1 review
- RR 1.29 [0.57, 2.91]3 studies · 1640 participantsLow
Neonatal vitamin A supplementation vs control
Vitamin A deficiency · mortality and morbidity in term neonates
Neonatal vitamin A supplementation showed no clear difference in vitamin A deficiency (serum retinol < 0.70 micromol/L) at 6 weeks of… compared with control (high certainty).
2 findings from 1 review
- Neonatal vitamin A supplementation for the prevention of mortality and morbidity in term neonates in low and middle… 2017 · Cochrane Headline outcomes onlyRR 0.94 [0.75, 1.19]1 study · 612 participantsHigh
- Neonatal vitamin A supplementation for the prevention of mortality and morbidity in term neonates in low and middle… 2017 · Cochrane Headline outcomes onlyRR 1.02 [0.64, 1.62]1 study · 369 participantsHigh
Staple foods fortified with vitamin A vs same unfortified staple foods
Subclinical vitamin A deficiency (serum/plasma retinol 70 μmol/L or less) · general population over 2 years of age
It is very uncertain whether staple foods fortified with vitamin A changes subclinical vitamin A deficiency (serum/plasma retinol 70 μmol/L or… compared with same unfortified staple foods (very low certainty).
1 finding from 1 review
- Fortification of staple foods with vitamin A for vitamin A deficiency 2019 · Cochrane Headline outcomes onlyRR 0.45 [0.19, 1.05]2 studies · 993 participantsVery low
Staple foods fortified with vitamin A vs same unfortified staple foods
Clinical vitamin A deficiency (as defined by night blindness) · general population over 2 years of age
It is very uncertain whether staple foods fortified with vitamin A changes clinical vitamin A deficiency (defined as night blindness) compared with same unfortified staple foods (very low certainty).
1 finding from 1 review
- Fortification of staple foods with vitamin A for vitamin A deficiency 2019 · Cochrane Headline outcomes onlyRR 0.11 [0.01, 1.98]1 study · 581 participantsVery low
Staple foods fortified with vitamin A vs same unfortified staple foods
Any adverse effects (e.g. hypervitaminosis A, as defined by the trialists) · general population over 2 years of age
The review found no eligible studies for this question.
1 finding from 1 review
- Fortification of staple foods with vitamin A for vitamin A deficiency 2019 · Cochrane Headline outcomes onlyno estimate extractedStudies not reportedNo studies found
Vitamin D vs placebo or no intervention
Cancer occurrence in trials using vitamin D₃ (cholecalciferol) · healthy participants or recruited among the general population; individuals diagnosed with a specific disease in a stable phase or with…
Vitamin D showed no clear difference in cancer occurrence in trials using vitamin D₃ (cholecalciferol) compared with placebo or no intervention (moderate certainty).
1 finding from 1 review
- RR 1 [0.94, 1.06]14 studies · 49891 participantsModerate
Vitamin D vs placebo or no intervention
Cancer mortality in trials using vitamin D3 (cholecalciferol) ( · healthy participants or recruited among the general population; individuals diagnosed with a specific disease in a stable phase or with…
Vitamin D may leads to lower cancer mortality in trials using vitamin D₃(cholecalciferol) compared with placebo or no intervention (low certainty).
1 finding from 1 review
- RR 0.88 [0.78, 0.98]4 studies · 44492 participantsLow
Vitamin D vs placebo or no intervention
Adverse events ‐ Nephrolithiasis in trials using vitamin D3 combined with calcium · healthy participants or recruited among the general population; individuals diagnosed with a specific disease in a stable phase or with…
Vitamin D may leads to higher adverse events: nephrolithiasis in trials using vitamin… compared with placebo or no intervention (low certainty).
1 finding from 1 review
- RR 1.17 [1.03, 1.34]3 studies · 42753 participantsLow
Staple food fortified with vitamin A plus other micronutrients vs no intervention
Subclinical vitamin A deficiency (serum/plasma retinol 0.70 μmol/L or less) · general population over 2 years of age
It is very uncertain whether staple food fortified with vitamin A plus other micronutrients changes subclinical vitamin A deficiency (serum/plasma retinol 0.70 μmol/L… compared with no intervention (very low certainty).
1 finding from 1 review
- Fortification of staple foods with vitamin A for vitamin A deficiency 2019 · Cochrane Headline outcomes onlyRR 0.71 [0.52, 0.98]2 studies · 318 participantsVery low
Staple food fortified with vitamin A plus other micronutrients vs no intervention
Clinical vitamin A deficiency (as defined by night blindness) · general population over 2 years of age
The review found no eligible studies for this question.
1 finding from 1 review
- Fortification of staple foods with vitamin A for vitamin A deficiency 2019 · Cochrane Headline outcomes onlyno estimate extractedStudies not reportedNo studies found
Staple food fortified with vitamin A plus other micronutrients vs no intervention
Any adverse effects (e.g. hypervitaminosis A, as defined by the trialists) · general population over 2 years of age
The review found no eligible studies for this question.
1 finding from 1 review
- Fortification of staple foods with vitamin A for vitamin A deficiency 2019 · Cochrane Headline outcomes onlyno estimate extractedStudies not reportedNo studies found
Staple food fortified with vitamin A plus other micronutrients vs same unfortified staple foods
Any adverse effects (e.g. hypervitaminosis A, as defined by the trialists) · general population over 2 years of age
The review found no eligible studies for this question.
1 finding from 1 review
- Fortification of staple foods with vitamin A for vitamin A deficiency 2019 · Cochrane Headline outcomes onlyno estimate extractedStudies not reportedNo studies found
Staple food fortified with vitamin A plus other micronutrients vs same unfortified staple foods
Subclinical vitamin A deficiency (serum/plasma retinol 0.70 μmol/L or less) · general population over 2 years of age
Staple foods fortified with vitamin A plus other micronutrients probably leads to lower subclinical vitamin A deficiency (serum/plasma retinol 0.70 μmol/L… compared with same unfortified staple foods (moderate certainty).
1 finding from 1 review
- Fortification of staple foods with vitamin A for vitamin A deficiency 2019 · Cochrane Headline outcomes onlyRR 0.27 [0.16, 0.49]3 studies · 923 participantsModerate
Staple food fortified with vitamin A plus other micronutrients vs same unfortified staple foods
Clinical vitamin A deficiency (as defined by night blindness) · general population over 2 years of age
The review found no eligible studies for this question.
1 finding from 1 review
- Fortification of staple foods with vitamin A for vitamin A deficiency 2019 · Cochrane Headline outcomes onlyno estimate extractedStudies not reportedNo studies found
Vitamin D given to infants vs vitamin D given to lactating mothers
Vitamin D insufficiency: 25‐OH vitamin D < 50 nmol/L · term breastfed infants to prevent vitamin D deficiency and improve bone health
It is very uncertain whether vitamin D given to infants changes vitamin D insufficiency: 25‐OH vitamin D < 50 nmol/L compared with vitamin D given to lactating mothers (very low certainty).
1 finding from 1 review
- Vitamin D supplementation for term breastfed infants to prevent vitamin D deficiency and improve bone health 2020 · Cochrane Headline outcomes onlyRR 0.61 [0.4, 0.94]4 studies · 334 participantsVery low
Vitamin D given to infants vs vitamin D given to lactating mothers
Vitamin D deficiency: 25‐OH vitamin D < 30 nmol/L · term breastfed infants to prevent vitamin D deficiency and improve bone health
It is very uncertain whether vitamin D given to infants changes vitamin D deficiency: 25‐OH vitamin D < 30 nmol/L compared with vitamin D given to lactating mothers (very low certainty).
1 finding from 1 review
- Vitamin D supplementation for term breastfed infants to prevent vitamin D deficiency and improve bone health 2020 · Cochrane Headline outcomes onlyRR 0.35 [0.17, 0.72]4 studies · 334 participantsVery low