All‐cause mortality Physicians · middle‐aged US male physicians
It is very uncertain whether vitamin C supplementation changes all‐cause mortality Physicians compared with placebo (very low certainty).
1 finding from 1 review
Fatal or nonfatal myocardial infarction · middle‐aged US male physicians
Vitamin C supplementation showed no clear difference in total myocardial infarction (fatal and non‐fatal) Physicians compared with placebo (low certainty).
1 finding from 1 review
Stroke · middle‐aged US male physicians
Vitamin C supplementation showed no clear difference in total stroke (fatal and non‐fatal) Physicians compared with placebo (low certainty).
1 finding from 1 review
Self‐reported CABG/PTCA Participant self‐reports · middle‐aged US male physicians
Vitamin C supplementation showed no clear difference in self‐reported CABG/PTCA Participant self‐reports compared with placebo (low certainty).
1 finding from 1 review
Self‐reported angina Participant self‐reports · middle‐aged US male physicians
Vitamin C supplementation showed no clear difference in self‐reported angina Participant self‐reports compared with placebo (low certainty).
1 finding from 1 review
Fasting blood glucose (mg/dL) · Adults with diabetes
Meta-analysis of randomised trials of vitamin D supplementation for Fasting glucose (Diabetes patients with normal glucose tolerance): WMD 0.01 (95% CI -0.21 to 0.23), not statistically significant. Umbrella review outcome-level evidence grade: Substantial effect unlikely.
2 findings from 1 review
WMD 0.01 [-0.21, 0.23]
Studies not reported
GRADE not reported
WMD -0.3 [-0.9, 0.3]
Studies not reported
GRADE not reported
Femoral neck bone mineral density (FN-BMD) · Older or community-dwelling adults
Meta-analysis of randomised trials of vitamin D supplementation for Bone mineral density in femoral neck, Community-dwelling adults: WMD 1.10 (95% CI 0.40 to 1.90), statistically significant. Umbrella review outcome-level evidence grade: Suggestive.
1 finding from 1 review
WMD 1.10 [0.40, 1.90]
8 studies
GRADE not reported
Lumbar spine bone mineral density (BMD) · Older or community-dwelling adults
Meta-analysis of randomised trials of vitamin D supplementation for Bone mineral density in lumbar spine, Community-dwelling adults: WMD 0.10 (95% CI -0.60 to 0.70), not statistically significant. Umbrella review outcome-level evidence grade: Substantial effect unlikely.
1 finding from 1 review
WMD 0.10 [-0.60, 0.70]
7 studies
GRADE not reported
Non‐vertebral fractures · Older or community-dwelling adults
Meta-analysis of randomised trials of vitamin D supplementation for Fractures: non-vertebral, People aged >65 years: RR 0.79 (95% CI 0.63 to 0.99), statistically significant. Umbrella review outcome-level evidence grade: Suggestive.
1 finding from 1 review
Muscle strength · Older or community-dwelling adults
Meta-analysis of randomised trials of vitamin D supplementation for Performance measures: muscle strength, Older adults: SMD -0.19 (95% CI -0.35 to -0.02), statistically significant. Umbrella review outcome-level evidence grade: Suggestive.
1 finding from 1 review
SMD -0.19 [-0.35, -0.02]
3 studies
GRADE not reported
Fractures: non-vertebral, non-hip · Older or community-dwelling adults
Meta-analysis of randomised trials of vitamin D supplementation for Fractures: non-vertebral, non-hip, Older women: OR 0.69 (95% CI 0.21 to 1.66), not statistically significant. Umbrella review outcome-level evidence grade: No conclusion.
1 finding from 1 review
OR 0.69 [0.21, 1.66]
2 studies
GRADE not reported
Diastolic blood pressure · Adults (general population)
Meta-analysis of randomised trials of vitamin D supplementation for Diastolic blood pressure: WMD -0.03 (95% CI -1.98 to 1.92), not statistically significant. Umbrella review outcome-level evidence grade: Suggestive.
1 finding from 1 review
WMD -0.03 [-1.98, 1.92]
3 studies
GRADE not reported
Gestational age at birth (weeks) · pregnant women
Meta-analysis of randomised trials of vitamin D supplementation for Mean gestational age at delivery: WMD 0.17 (95% CI -0.16 to 0.51), not statistically significant. Umbrella review outcome-level evidence grade: No conclusion.
1 finding from 1 review
WMD 0.17 [-0.16, 0.51]
2 studies
GRADE not reported
Small‐for‐gestational age · pregnant women
Meta-analysis of randomised trials of vitamin D supplementation for Small for gestational age: RR 0.67 (95% CI 0.40 to 1.11), not statistically significant. Umbrella review outcome-level evidence grade: Suggestive.
1 finding from 1 review
Bone mineral density in forearm · children
Meta-analysis of randomised trials of vitamin D supplementation for Bone mineral density in forearm, Healthy children: SMD 0.04 (95% CI -0.36 to 0.45), not statistically significant. Umbrella review outcome-level evidence grade: Substantial effect unlikely.
1 finding from 1 review
SMD 0.04 [-0.36, 0.45]
3 studies
GRADE not reported
Preterm birth · pregnant women
Meta-analysis of randomised trials of vitamin D supplementation for Preterm delivery: RR 0.77 (95% CI 0.35 to 1.66), not statistically significant.
1 finding from 1 review
Fractures: vertebral or deformity · Older or community-dwelling adults
Meta-analysis of randomised trials of vitamin D supplementation for Fractures: vertebral or deformity, Men aged >65 years and postmenopausal women: RR 0.90 (95% CI 0.42 to 1.92), not statistically significant. Umbrella review outcome-level evidence grade: No conclusion.
1 finding from 1 review
Bone mineral density in forearm · Community dwelling adults
The meta-analysis of RCTs reported a WMD of -0.70 (95% CI 1.70 to 0.40) for vitamin d supplementation versus control.
1 finding from 1 review
WMD -0.70 [-1.70, 0.40]
2 studies
GRADE not reported
Cholesterol mg/dL · Adults (general population)
Meta-analysis of randomised trials of vitamin D supplementation for Total cholesterol: WMD 1.52 (95% CI -1.42 to 4.46), not statistically significant. Umbrella review outcome-level evidence grade: No conclusion.
1 finding from 1 review
WMD 1.52 [-1.42, 4.46]
11 studies
GRADE not reported
Mortality (all cause) · Adults (general population)
Meta-analysis of randomised trials of vitamin D supplementation for Mortality (all cause) (Vitamin D2, general population): RR 1.04 (95% CI 0.97 to 1.11), not statistically significant. Umbrella review outcome-level evidence grade: No conclusion.
2 findings from 1 review