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Cited by 461Vitamin C and Antioxidants ResearchAntioxidant Activity and Oxidative StressExercise and Physiological Responses

Vitamin C and Infections

Open access
Hemilä, Harri·2017·Nutrients
DOI 10.3390/nu9040339PMC PMC5409678
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Abstract

In the early literature, vitamin C deficiency was associated with pneumonia. After its identification, a number of studies investigated the effects of vitamin C on diverse infections. A total of 148 animal studies indicated that vitamin C may alleviate or prevent infections caused by bacteria, viruses, and protozoa. The most extensively studied human infection is the common cold. Vitamin C administration does not decrease the average incidence of colds in the general population, yet it halved the number of colds in physically active people. Regularly administered vitamin C has shortened the duration of colds, indicating a biological effect. However, the role of vitamin C in common cold treatment is unclear. Two controlled trials found a statistically significant dose–response, for the duration of common cold symptoms, with up to 6–8 g/day of vitamin C. Thus, the negative findings of some therapeutic common cold studies might be explained by the low doses of 3–4 g/day of vitamin C. Three controlled trials found that vitamin C prevented pneumonia. Two controlled trials found a treatment benefit of vitamin C for pneumonia patients. One controlled trial reported treatment benefits for tetanus patients. The effects of vitamin C against infections should be investigated further.

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Crossref · 10.3390/nu9040339

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166 of 166 references verified0 citation errors · 0 not checkable

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  • Notwithstanding that the effect is absent in the general population, vitamin C can be effective under specific conditions, such as low levels of vitamin C, e.g., in people under physical stress.

    “Notwithstanding that the effect is absent in the general population, vitamin C can be effective under specific conditions, such as low levels of vitamin C, e.g., in people under physical stress [6,191,195,198].”

    From Vitamin C-Sources, Physiological Role, Kinetics, Deficiency, Use, Toxicity, and Determination (2021) · cites this paper as [195]

    Section 4.4 reports no change in average common-cold incidence in general-community trials, while Section 4.3 reports fewer colds among participants under heavy short-term physical activity. Section 2.5 suggests supplementation may have greater effects when baseline vitamin C is low. The paper does not establish that people under physical stress have low vitamin C levels, and its general-community finding concerns average cold incidence rather than every possible effect. (LLM, conf=0.82)

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  • Animal models have largely shown a protective effect of vitamin C on different infections or intoxications with bacterial toxins.

    “and animal models have largely shown a protective effect of vitamin C on different infections or intoxications with bacterial toxins [155,195].”

    From Vitamin C-Sources, Physiological Role, Kinetics, Deficiency, Use, Toxicity, and Determination (2021) · cites this paper as [195]

  • Patients with infections have lower levels of vitamin C.

    “Patients with infections have lower levels of vitamin C”

    From Vitamin C-Sources, Physiological Role, Kinetics, Deficiency, Use, Toxicity, and Determination (2021) · cites this paper as [195]

  • In those under physical stress (e.g., at work, during sports, and under extreme temperatures), or in cases where vitamin C levels are slightly below recommended levels, vitamin C supplementation reduces common cold incidence.

    “In those under physical stress (e.g., at work, during sports, and under extreme temperatures) [104], or in cases where vitamin C levels are slightly below recommended levels, vitamin C supplementation reduces common cold incidence.”

    From Immune function and micronutrient requirements change over the life course (2018) · cites this paper as [104]

  • A low vitamin C status also increases susceptibility to infections such as pneumonia, possibly because low levels of antioxidants such as vitamin C are unable to counteract the oxidative stress observed in pneumonia.

    “A low vitamin C status also increases susceptibility to infections such as pneumonia [71], possibly because low levels of antioxidants such as vitamin C are unable to counteract the oxidative stress observed in pneumonia [104].”

    From Immune function and micronutrient requirements change over the life course (2018) · cites this paper as [104]

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Research works printed but not linked: 4

  1. [2]Carpenter K.J. The History of Scurvy and Vitamin C Cambridge University Press Cambridge, UK 1986
  2. [14]Food and Nutrition Board Food and Nutrition Board, Institute of Medicine: Dietary Reference Intakes for Vitamin C, Vitamin E, Selenium and Carotenoids National Academy Press Washington, DC, USA 2000 95 185 25077263
  3. [67]Ritzel G. Critical analysis of the role of vitamin C in the treatment of the common cold Helv. Med. Acta 1961 28 63 68 (In German) 13741912
  4. [95]Miegl H. Acute upper respiratory tract infection and its treatment with vitamin C Wien. Med. Wochenschr. 1957 107 989 992 (In German) 13531063

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Authors
Hemilä, H.
Affiliations
University of Helsinki (FI)
Corresponding author
Hemilä, Harri
ORCID
Hemilä, Harri
Venue
Nutrients
Publisher
MDPI AG
Published
2017-03-29
Volume
9
Issue
4
Pages
339
ISSN
2072-6643 (ISSN-L)
DOI
10.3390/nu9040339
PMC
PMC5409678
OpenAlex
W2601577524
Cited by
461
References
166
Citations by year
2026: 13 · 2025: 33 · 2024: 40 · 2023: 54 · 2022: 72 · 2021: 87 · 2020: 114 · 2019: 21 · 2018: 22 · 2017: 5
FWCI
4.56
Type
journal article
Language
en
Open access
Licence
Locations
  • Nutrients (publishedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • Työväentutkimus Vuosikirja (submittedVersion)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
Funders
  • Helsingin Yliopisto
  • Ella ja Georg Ehrnroothin Säätiö
  • Juho Vainion Säätiö
Topics
  • Health Sciences › Nursing › Nutrition and Dietetics › Vitamin C and Antioxidants Research
  • Health Sciences › Medicine › Biochemistry › Antioxidant Activity and Oxidative Stress
  • Health Sciences › Medicine › Rehabilitation › Exercise and Physiological Responses
Keywords
vitamin C, common cold, pneumonia, tetanus, bacterial infection, viral infection, protozoan infection, infection control, dose-response relationship, scurvy
MeSH terms
Animals, Ascorbic Acid, Ascorbic Acid Deficiency, Common Cold, Humans, Pneumonia, Tetanus, Vitamins

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