What do systematic reviews say?

Summary of findings: fat‐soluble vitamin E vs control

• Vitamin E supplementation in people with cystic fibrosis 2020 · Cochrane Headline outcomes only
  no estimate extracted
  6 participants
  GRADE not reported

Summary of findings: water‐soluble vitamin E vs control

The review found no eligible studies for this question.

• Vitamin E supplementation in people with cystic fibrosis 2020 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Summary of findings: water‐soluble vitamin E vs control

Summary of findings: water‐soluble vitamin E may leads to higher vitamin E levels in serum: umol/L compared with control (low certainty).

• Vitamin E supplementation in people with cystic fibrosis 2020 · Cochrane Headline outcomes only
  MD 19.74 [13.48, 26]
  1 study · 45 participants
  Low

Summary of findings: water‐soluble vitamin E vs control

The review found no eligible studies for this question.

• Vitamin E supplementation in people with cystic fibrosis 2020 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Summary of findings: water‐soluble vitamin E vs control

The review found no eligible studies for this question.

• Vitamin E supplementation in people with cystic fibrosis 2020 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Staple food fortified with vitamin A plus other micronutrients vs no intervention

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).

• Fortification of staple foods with vitamin A for vitamin A deficiency 2019 · Cochrane Headline outcomes only
  RR 0.71 [0.52, 0.98]
  2 studies · 318 participants
  Very low

Staple food fortified with vitamin A plus other micronutrients vs no intervention

The review found no eligible studies for this question.

• Fortification of staple foods with vitamin A for vitamin A deficiency 2019 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Staple food fortified with vitamin A plus other micronutrients vs no intervention

The review found no eligible studies for this question.

• Fortification of staple foods with vitamin A for vitamin A deficiency 2019 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Staple food fortified with vitamin A plus other micronutrients vs same unfortified staple foods

The review found no eligible studies for this question.

• Fortification of staple foods with vitamin A for vitamin A deficiency 2019 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Staple food fortified with vitamin A plus other micronutrients vs same unfortified staple foods

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).

• Fortification of staple foods with vitamin A for vitamin A deficiency 2019 · Cochrane Headline outcomes only
  RR 0.27 [0.16, 0.49]
  3 studies · 923 participants
  Moderate

Staple food fortified with vitamin A plus other micronutrients vs same unfortified staple foods

The review found no eligible studies for this question.

• Fortification of staple foods with vitamin A for vitamin A deficiency 2019 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Vitamin E vs placebo

It is very uncertain whether vitamin E changes progression to late AMD (neovascular AMD, geographic atrophy or both) compared with placebo (very low certainty).

• Antioxidant vitamin and mineral supplements for slowing the progression of age‐related macular degeneration 2023 · Cochrane Headline outcomes only
  RR 1.36 [0.31, 6.05]
  1 study · 998 participants
  Very low

Vitamin E vs placebo

The review found no eligible studies for this question.

• Antioxidant vitamin and mineral supplements for slowing the progression of age‐related macular degeneration 2023 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Vitamin E vs placebo

The review found no eligible studies for this question.

• Antioxidant vitamin and mineral supplements for slowing the progression of age‐related macular degeneration 2023 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Vitamin E vs placebo

Vitamin E showed no clear difference in progression to visual loss (loss of 3 or more lines on logMAR chart) compared with placebo (low certainty).

• Antioxidant vitamin and mineral supplements for slowing the progression of age‐related macular degeneration 2023 · Cochrane Headline outcomes only
  RR 1.04 [0.74, 1.47]
  1 study · 1179 participants
  Low

Vitamin E vs placebo

The review found no eligible studies for this question.

• Antioxidant vitamin and mineral supplements for slowing the progression of age‐related macular degeneration 2023 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Vitamin E vs placebo

It is very uncertain whether vitamin E changes adverse effects compared with placebo (very low certainty).

• Antioxidant vitamin and mineral supplements for slowing the progression of age‐related macular degeneration 2023 · Cochrane Headline outcomes only
  no estimate extracted
  4 participants
  Very low

Vitamin E vs placebo

The review found no eligible studies for this question.

• Antioxidant vitamin and mineral supplements for slowing the progression of age‐related macular degeneration 2023 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Vitamin C vs placebo

It is very uncertain whether vitamin C changes incidence of pneumonia Defined as patient admitted to hospital with… compared with placebo (very low certainty).

• Vitamin C supplementation for prevention and treatment of pneumonia 2021 · Cochrane Headline outcomes only
  RR 0.15 [0.02, 1.2]
  1 study · 674 participants
  Very low

Vitamin C vs placebo

The review found no eligible studies for this question.

• Vitamin C supplementation for prevention and treatment of pneumonia 2021 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found