ArticleEuropean journal of clinical nutrition2022
The role of vitamin C in pneumonia and COVID-19 infection in adults with European ancestry: a Mendelian randomisation study.
Article in European journal of clinical nutrition, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 17 papers, 4 of them syntheses that pooled it.
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Who cites it
17 citing papers in PubMed, 4 syntheses or guidelines pooled it, 28 citations in OpenAlex.
- Micronutrients, Vitamin D, and Inflammatory Biomarkers in COVID-19: A Systematic Review and Meta-analysis of Causal Inference Studies.Nutrition reviews · 2025Pooled it
- Vitamin C reduces the severity of common colds: a meta-analysis.BMC public health · 2023Pooled it
- Identifying factors contributing to increased susceptibility to COVID-19 risk: a systematic review of Mendelian randomization studies.International journal of epidemiology · 2022Pooled it
- COVID-19-Associated acute respiratory distress syndrome (CARDS): Mechanistic insights on therapeutic intervention and emerging trends.International immunopharmacology · 2021Pooled it
- No Genetically Predicted Association Between Human Papillomavirus and COVID-19: A Mendelian Randomization Analysis in European Ancestry Population.International journal of women's health · 2026Article
- The Role of Vitamins, Magnesium, and Trace Elements in COVID-19 Treatment and Post-COVID-19 Rehabilitation: An Updated Overview.Current medicinal chemistry · 2025Review
- Causality between COVID-19 and multiple myeloma: a two-sample Mendelian randomization study and Bayesian co-localization.Clinical and experimental medicine · 2024Article
- Prenol, but Not Vitamin C, of Fruit Binds to SARS-CoV-2 Spike S1 to Inhibit Viral Entry: Implications for COVID-19.Journal of immunology (Baltimore, Md. : 1950) · 2023Article
- The effects of vitamin C on respiratory, allergic and immunological diseases: an experimental and clinical-based review.Inflammopharmacology · 2023Review
- No genetic causal association between systemic lupus erythematosus and COVID-19.Frontiers in immunology · 2023Article
- The Role of Vitamin C: From Prevention of Pneumonia to Treatment of Covid-19.Materials today. Proceedings · 2022Article
- Assessment of vitamin C effects on pneumonia and COVID-19 using Mendelian randomization: analysis may be misleading.European journal of clinical nutrition · 2022Article
- Nutritional priorities in patients with severe COVID-19.Current opinion in clinical nutrition and metabolic care · 2022Review
- The Effect of Circulating Zinc, Selenium, Copper and Vitamin KNutrients · 2022Article
- Bias against Vitamin C in Mainstream Medicine: Examples from Trials of Vitamin C for Infections.Life (Basel, Switzerland) · 2022Review
- Repurposing of Chemotherapeutics to Combat COVID-19.Current topics in medicinal chemistry · 2022Article
- Relationship Between Plasma Vitamin C and COVID-19 Susceptibility and Severity: A Two-Sample Mendelian Randomization Study.Frontiers in medicine · 2022Article
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Authors and funding
4 authors at 3 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundHigh dose vitamin C infusion has been proposed to treat critically ill patients, including patients with pneumonia and severe COVID-19. However, trials have shown mixed findings. Here we assessed the unconfounded associations of vitamin C with COVID-19 and pneumonia using the Mendelian randomisation approach.
methodsThis is a separate-sample Mendelian randomisation study using publicly available data. We applied single nucleotide polymorphisms (SNPs) that were associated with plasma vitamin C, in a recent genome-wide association study (GWAS) as genetic instruments to the GWAS of severe COVID-19, COVID-19 hospitalisation and any infection in the COVID-19 host genetics initiative and the GWAS of pneumonia in the UK Biobank, to assess whether people with genetically predicted higher levels of plasma vitamin C had lower risk of severe COVID-19 and pneumonia.
resultsGenetically predicted circulating levels of vitamin C was not associated with susceptibility to severe COVID-19, COVID-19 hospitalisation, any COVID-19 infection nor pneumonia. Similar results were obtained when a weighted median and MR-Egger methods were used.
conclusionsMendelian randomisation analysis provided little evidence for an association of genetically predicted circulating levels of vitamin C with COVID-19 or pneumonia and thus our findings provided little support to the use of vitamin C in prevention and treatment in these patients, unless high dose vitamin C infusion has therapeutic effects via different biological pathways.
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