Vitamin D supplementation to prevent acute respiratory tract infections: systematic review and meta-analysis of individual participant data.
Martineau AR, Jolliffe DA, Hooper RL, Greenberg L, Aloia JF, Bergman Pet al.
BMJ · 2017:i6583
This study evaluates Vitamin D supplements given by mouth in various doses (daily, weekly, or monthly) compared with placebo or no vitamin D in relation to Occurrence of any acute respiratory tract infection (such as colds, flu, or bronchitis).
Evidence-Based Research: Vitamin D Immunity Bmj
Key facts at a glance
- DOI
- 10.1136/bmj.i6583
- PMID
- 28202713
- PMC
- PMC5310969
- Journal
- BMJ
- Year
- 2017
- Pages
- i6583
- Study type
- meta-analysis
- Evidence level
- Ia
- Sample size
- 11321
- Intervention
- Vitamin D supplements given by mouth in various doses (daily, weekly, or monthly) compared with placebo or no vitamin D
- Primary outcome
- Occurrence of any acute respiratory tract infection (such as colds, flu, or bronchitis)
- Follow-up
- Varied by trial (median around 6 months, range 1 month to several years)
- Funding
- government
- Effect size
- Adjusted odds ratio 0.88 (95% CI 0.81-0.96) overall; stronger benefit (OR 0.30) in those with severe deficiency
- Registration
- CRD42014013953
- Open access
- true
Study Overview
This study examined the effects of Vitamin D supplements given by mouth in various doses (daily, weekly, or monthly) compared with placebo or no vitamin D on Occurrence of any acute respiratory tract infection (such as colds, flu, or bronchitis).
Key Findings
The results suggest the intervention has potential clinical benefits.
Clinical Conclusions
See original publication.
Abstract
"This meta-analysis enrolled 11,321 participants, investigating the effects of Vitamin D supplements given by mouth in various doses (daily, weekly, or monthly) compared with placebo or no vitamin D on Occurrence of any acute respiratory tract infection (such as colds, flu, or bronchitis).
Funding & conflicts of interest
Funding: government
COI: Some authors reported research grants or advisory roles linked to vitamin D; full disclosures provided in the paper
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Medically reviewed by WellAlly Editorial Team Last reviewed July 22, 2026. · Read our editorial policy