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Opinion or narrative review

Review of vitamin D and COVID-19 found no clear support for routine supplement use

Martineau · The Proceedings of the Nutrition Society · 2023

Original title: Vitamin D in the prevention or treatment of COVID-19.

Under review. A person has not yet checked this summary against the paper. It is written from the PubMed abstract. Until a person checks it, search engines are asked not to list this page.

What the study found

No difference

Observational studies link higher vitamin D to lower COVID-19 risk, but genetic studies were null and trials were inconsistent. Current evidence is insufficient to support routine use of vitamin D supplements for COVID-19.

The study at a glance

Type of study
Opinion or narrative review
Who or what was studied
People at risk of or sick with COVID-19
What was tested
Review of vitamin D supplements and blood levels for preventing or treating COVID-19
Trial registration
NCT04641195
Who has a stake
No disclosure in PubMed
No disclosure in PubMed.
Journal
The Proceedings of the Nutrition Society, 2023
Source
PubMed record 36366796. This page is based on the abstract only.

How much this study counts

  • –An opinion or narrative review: no new data, and no set method for choosing which studies to discuss.
  • •The PubMed record has no conflict-of-interest statement.
  • •Summarized from the PubMed abstract only. The full paper may hold details the abstract leaves out.

✓ Strength– Limit• Note

These points come from fixed rules about the type of study, its size and length, what it measured, and who has a stake. Every study on Digestery gets the same rules.

Where this study sits

This paper is not on the ladder. It is a opinion or narrative review, and reviews and opinion pieces discuss studies that are already counted on the steps below.

↑ Stronger evidence

  1. Trials in people: colds, flu and chest infections

    10

    2 benefit, 8 no difference

  2. Trials in people: other measures

    5

    1 benefit, 1 mixed, 2 no difference, 1 harm

  3. Trials in people: lab tests or safety

    1

    1 no difference

  4. Population studies

    1

    1 no difference

  5. Blood levels and genes

    4

    3 benefit, 1 no difference

↓ Weaker evidence

  • Points to benefit
  • Mixed
  • No difference
  • No direction
  • Points to harm

How it fits with the other research

The short answer to “Does vitamin D prevent colds and infections?”

Not clearly; any effect looks small.

Confidence: low. Based on 33 on-topic papers.

Read the full answer

Other opinion on this question

See all 33 studies on this question

How this page was made

Label

First read of the abstract
Claude Sonnet
Independent second read
Claude Haiku
Differences settled
The two reads differed. The reviewer checked the abstract and kept the first read. Claude Opus 5.5.
Headline
Claude Sonnet, from the checked study record. A script checked its numbers and wording.
Numbers
Checked against the abstract by a script
“How much this study counts”
Fixed rules, the same for every study
Source check by a person
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