What do systematic reviews say?

Vitamin D vs placebo/no treatment

• Vitamin D for the treatment of inflammatory bowel disease 2023 · Cochrane Headline outcomes only
  no estimate extracted
  2 studies · 243 participants
  Very low

Antioxidant multivitamin and mineral supplement vs placebo or no treatment

• Antioxidant vitamin and mineral supplements for slowing the progression of age‐related macular degeneration 2023 · Cochrane Headline outcomes only
  no estimate extracted
  1 study · 110 participants
  Low

Steroid plus vitamin D vs steroids

• Topical treatments for scalp psoriasis 2016 · Cochrane Headline outcomes only
  no estimate extracted
  0 studies · 0 participants
  GRADE not reported

Vitamin D vs placebo or usual care

The review found no eligible studies for this question.

• Vitamin D supplementation for the treatment of COVID‐19: a living systematic review 2021 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Vitamin C vs placebo

• Vitamin C for asthma and exercise‐induced bronchoconstriction 2013 · Cochrane Headline outcomes only
  no estimate extracted
  1 study · 201 participants
  Low

Vitamin C vs placebo

The review found no eligible studies for this question.

• Vitamin C for asthma and exercise‐induced bronchoconstriction 2013 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

hAMMSC‐CM + vitamin C vs hAMMSC‐CM

The review found no eligible studies for this question.

• Interventions for ulceration and other skin changes caused by nerve damage in leprosy 2019 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

hAMMSC‐CM + vitamin E vs hAMMSC‐CM

The review found no eligible studies for this question.

• Interventions for ulceration and other skin changes caused by nerve damage in leprosy 2019 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Magnesium and vitamin E co‐supplementation vs placebo

The review found no eligible studies for this question.

• Nutritional interventions for treating foot ulcers in people with diabetes 2020 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Summary of findings: oral vitamin E supplementation vs placebo or no treatment

The review found no eligible studies for this question.

• Antioxidant supplementation for lung disease in cystic fibrosis 2019 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Vitamin K antagonist (VKA) prophylaxis vs no prophylaxis

The review found no eligible studies for this question.

• Oral anticoagulation in people with cancer who have no therapeutic or prophylactic indication for anticoagulation 2021 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Oral nutritional supplements vs placebo

The review found no eligible studies for this question.

• Nutritional interventions for treating foot ulcers in people with diabetes 2020 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Topical vitamin D derivative vs placebo

The review found no eligible studies for this question.

• Interventions for chronic palmoplantar pustulosis 2020 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Oral vs intramuscular vitamin B12

The review found no eligible studies for this question.

• Oral vitamin B₁₂ versus intramuscular vitamin B₁₂ for vitamin B₁₂ deficiency 2018 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Angiotensin‐converting enzyme inhibitors vs vitamin C

The review found no eligible studies for this question.

• Interventions for chronic kidney disease in people with sickle cell disease 2023 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Steroids vs vitamin D

• Topical treatments for scalp psoriasis 2016 · Cochrane Headline outcomes only
  no estimate extracted
  0 studies · 0 participants
  GRADE not reported

Lutein with or without zeaxanthin vs placebo

• Antioxidant vitamin and mineral supplements for slowing the progression of age‐related macular degeneration 2023 · Cochrane Headline outcomes only
  no estimate extracted
  2 studies · 308 participants
  Moderate

Zinc 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

Calcium vs placebo

The review found no eligible studies for this question.

• Calcium and vitamin D for increasing bone mineral density in premenopausal women 2023 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Direct oral anticoagulant secondary prophylaxis vs vitamin K antagonist secondary prophylaxis

• Anticoagulation for the long‐term treatment of venous thromboembolism in people with cancer 2018 · Cochrane Headline outcomes only
  no estimate extracted
  1 study · 8485 participants
  Moderate