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Vitamin C for COVID-19
72 studies from 777 scientists
88,913 patients in 22 countries
Statistically significant lower risk for mortality, ICU, hospitalization, and recovery.
20% lower risk in 21 RCTs CI 9-30%
14% lower mortality in 14 RCTs CI -2-28%
COVID-19 Vitamin C studies. Jul 2024.
0 0.5 1 1.5+ All studies 21% With exclusions 26% Mortality 19% Hospitalization 19% Recovery 29% Cases 3% Viral clearance -5% RCTs 20% RCT mortality 14% High dose IV 21% Symptomatic 24% Prophylaxis 19% Early 39% Late 20% Favorsvitamin C Favorscontrol
Home   Post   Share   @CovidAnalysis   Meta AnalysisMeta   The European Food Safety Authority has found evidence for a causal relationship between the intake of vitamin C and optimal immune system function Galmés, Galmés (B). Recent:
Vitamin C was adopted in all or part of 12 countries. Submit updates/corrections. Summary.
Jul 23
Covid Analysis Vitamin C for COVID-19: real-time meta analysis of 74 studies (72 treatment studies and 2 sufficiency studies)
Statistically significant lower risk is seen for mortality, ICU admission, hospitalization, and recovery. 24 studies from 24 independent teams in 12 countries show significant improvements. Meta analysis using the most serious outcome rep..
Jul 8
Corrao et al., Journal of Clinical Medicine, doi:10.3390/jcm13133987 Safety of High-Dose Vitamin C in Non-Intensive Care Hospitalized Patients with COVID-19: An Open-Label Clinical Study
39% lower mortality (p=0.37), 19% lower combined mortality/ICU admission (p=0.24), 102% higher ICU admission (p=0.51), and 25% shorter hospitalization (p=0.16). Prospective study of 146 hospitalized COVID-19 patients showing shorter hospitalization with high-dose intravenous vitamin C. 104 patients received 10g of vitamin C intravenously daily for 3 days and 42 patients received only standard car..
May 22
Guan et al., The American Journal of the Medical Sciences, doi:10.1016/j.amjms.2024.05.005 High-dose Vitamin C Intake and COVID-19 Related Symptoms During the SARS-CoV-2 Pandemic
31% fewer symptomatic cases (p=0.007). Retrospective 2,746 individuals in China showing significantly lower incidence of COVID-19 symptoms and fever with higher vitamin C intake, with a dose response relationship.
May 21
Hemilä et al., Frontiers in Medicine, doi:10.3389/fmed.2024.1391346 Rebound effect explains the divergence in survival after 5 days in a controlled trial on vitamin C for COVID-19 patients
Reanalysis of the REMAP-CAP and LOVIT-COVID vitamin C RCTs [Adhikari] showing that the poor results may be explained by a rebound effect due to the abrupt termination of vitamin C treatment after 4 days. Authors describe a rebound effect ..
Apr 16
Agamah et al., ScienceOpen, doi:10.58647/DRUGARXIV.PR000010.v1 Network-based multi-omics-disease-drug associations reveal drug repurposing candidates for COVID-19 disease phases
In Silico study identifying potential drugs beneficial for COVID-19 by integrating transcriptomics, proteomics, metabolomics, lipidomics, and drug data. Authors explore interactions between drugs, molecular features, and disease severity...
Apr 4
Fowler et al., NCT04344184 SAFEty Study of Early Infusion of Vitamin C for Treatment of Novel Coronavirus Acute Lung Injury (SAFE EVICT CORONA-ALI)
19% lower mortality (p=0.75) and 2% worse results (p=0.28). RCT 47 ICU patients showing no significant differences with vitamin C treatment.
Mar 24
Mosadegh et al., AMB Express, doi:10.1186/s13568-024-01690-8 NBS superfood: a promising adjunctive therapy in critically ill ICU patients with omicron variant of COVID-19
RCT 400 critically ill ICU patients with omicron-related ARDS showing significantly reduced mortality and inflammatory markers with a nutritional supplement containing vitamins A, B1–B3, B5, B6, B9, C, D, K, and zinc, potassium, manganese..
Mar 13
Arboleda et al., Behavioural Public Policy, doi:10.1017/bpp.2024.11 EAST framework to promote adherence to nutritional supplementation: a strategy to mitigate COVID-19 within health workers
36% fewer cases (p=0.03). Prospective study of 1,063 health workers in Colombia showing lower COVID-19 infection rates with adherence to a vitamin D and C supplementation plan, however very limited baseline information is provided for the adherent vs. non-adherent..
Mar 4
Kow et al., International Journal of Pharmacy Practice, doi:10.1093/ijpp/riae003 Impact of uricosurics on mortality outcomes in patients with COVID-19: a systematic review and meta-analysis of randomized controlled trials
50% lower mortality (p=0.008). Systematic review and meta analysis of 27 RCTs investigating the impact of uricosuric drugs on mortality in COVID-19 patients. The pooled analysis found no significant association between uricosuric use and mortality risk. However, a subg..
Jan 30
Chanyandura et al., J. Basic Appl. Pharm. Sci., doi:10.33790/jbaps1100105 Evaluation of The Pharmaceutical Quality of the Most Commonly Purchased Vitamin C (Ascorbic Acid) Formulations in COVID-19 Infection in South Africa
Analysis of commonly purchased vitamin C supplements in South Africa during the COVID-19 pandemic finding that vitamin C tablets failed quality tests like friability and had only 18% of the labelled vitamin C content, however vitamin C ca..
Dec 20
Chiscano-Camón et al., Frontiers in Medicine, doi:10.3389/fmed.2023.1301001 Vitamin C deficiency in critically ill COVID-19 patients admitted to intensive care unit
Observational study of 43 critically ill COVID-19 patients requiring respiratory support showing vitamin C deficiency present at ICU admission and persisting throughout ICU stay. 86% of patients had undetectable vitamin C levels (<1.5mg/L..
Dec 11
Hemilä et al., BMC Public Health, doi:10.1186/s12889-023-17229-8 Vitamin C reduces the severity of common colds: a meta-analysis
Meta-analysis of 10 placebo-controlled trials showing that vitamin C treatment reduces the severity and duration of the common cold, with a greater effect on more severe outcomes.
Dec 11
Morales-Bayuelo et al., F1000Research, doi:10.12688/f1000research.123550.3 New findings on ligand series used as SARS-CoV-2 virus inhibitors within the frameworks of molecular docking, molecular quantum similarity and chemical reactivity indices
In Silico analysis showing that vitamin C can stably bind within the SARS-CoV-2 RNA-dependent RNA polymerase binding pocket. Notable stabilizing interactions were seen between vitamin C and residue lysine 621, similar to the antiviral rem..
Nov 15
Moatasim et al., Microorganisms, doi:10.3390/microorganisms11112777 Potent Antiviral Activity of Vitamin B12 against Severe Acute Respiratory Syndrome Coronavirus 2, Middle East Respiratory Syndrome Coronavirus, and Human Coronavirus 229E
In Vitro and In Silico analysis finding that methylcobalamin, hydroxocobalamin, and cyanocobalamin forms of vitamin B12 showed broad-spectrum inhibition against SARS-CoV-2, MERS-CoV, and HCoV-229E. Methylcobalamin had the highest activity..
Nov 8
Rahman et al., Molecular Mechanism Research, 1:1 Clinical & Demographical Status of Hospitalized and Non-Hospitalized Covid-19 Cases: A Multicenter Hospital Based Study in Bangladesh
40% lower hospitalization (p=0.0001). Retrospective 416 non-hospitalized and 184 hospitalized COVID-19 patients in Bangladesh, showing higher acetaminophen and lower vitamin C usage for hospitalized patients. Confounding may be significant and baseline details per treatment g..
Nov 7
Akbar et al., Nutrients, doi:10.3390/nu16071037 The Association between Lifestyle Factors and COVID-19: Findings from Qatar Biobank
14% fewer cases (p=0.29). Retrospective 10,000 adults in Qatar, showing lower risk of COVID-19 cases with vitamin C supplementation, without statistical significance. Authors do not analyze COVID-19 severity.
Oct 25
Adhikari et al., JAMA, doi:10.1001/jama.2023.21407 Intravenous Vitamin C for Patients Hospitalized With COVID-19 Two Harmonized Randomized Clinical Trials
Very late stage (APACHE II 8 and 12 for non-critical and critical) RCT with publication delayed over a year showing higher ventilation and no significant difference in mortality with vitamin C. Authors have combined what was to be two sep..
Oct 25
Adhikari et al., JAMA, doi:10.1001/jama.2023.21407 Intravenous Vitamin C for Patients Hospitalized With COVID-19 Two Harmonized Randomized Clinical Trials
Very late stage (APACHE II 8 and 12 for non-critical and critical) RCT with publication delayed over a year showing higher ventilation and no significant difference in mortality with vitamin C. Authors have combined what was to be two sep..
Oct 6
Ahmed et al., International Journal of Diabetes Management, doi:10.61797/ijdm.v2i2.259 Evaluation of the Effect of Zinc, Quercetin, Bromelain and Vitamin C on COVID-19 Patients
Case series of 22 hospitalized COVID-19 patients showing that a combination of quercetin 800mg, bromelain 165mg, zinc acetate 50mg and vitamin C 1g daily for 3-5 days was safe when given with other treatments. Authors include In Silico mo..
Sep 22
Seely et al., BMJ Open, doi:10.1136/bmjopen-2023-073761 Dietary supplements to reduce symptom severity and duration in people with SARS-CoV-2: a double-blind randomised controlled trial
14% improved recovery (p=0.41). Early terminated low-risk population (no hospitalization) very late treatment (mean 8 days) RCT with 44 patients treated with vitamin C, D, K, and zinc, and 46 control patients, showing no significant differences. Authors acknowledge that..
Sep 13
Albóniga et al., Scientific Reports, doi:10.1038/s41598-023-40999-5 Differential abundance of lipids and metabolites related to SARS-CoV-2 infection and susceptibility
Plasma metabolomic analysis showing significantly lower threonic acid levels for severe and mild COVID-19 cases compared with moderate cases. Threonic acid is a metabolite of vitamin C. The expected relationship in non-linear and depends ..
Sep 8
Sun et al., Nutrition Reviews, doi:10.1093/nutrit/nuad105 Therapeutic effects of high-dose vitamin C supplementation in patients with COVID-19: a meta-analysis
66% lower progression (p=0.03). Meta analysis of 14 studies showing lower COVID-19 progression with high-dose vitamin C treatment.
Aug 25
Alkafaas et al., Virology Journal, doi:10.1186/s12985-023-02160-6 A study on the effect of natural products against the transmission of B.1.1.529 Omicron
Review of natural products for SARS-CoV-2 omicron including an In Silico study showing quercetin, curcumin, ascorbic acid, nigellidine, and chloroquine among many compounds docked to the ACE2 metallopeptidase domain. Quercetin, curcumin, ..
Aug 20
Boerenkamp et al., Nutrients, doi:10.3390/nu15163653 Low Levels of Serum and Intracellular Vitamin C in Hospitalized COVID-19 Patients
56% lower severe cases (p=0.1). Analysis of serum and intracellular vitamin C levels in hospitalized COVID-19 patients. Low vitamin C levels were common with 36% having serum levels <26 μmol/L and 15% <11 μmol/L. Intracellular vitamin C levels in peripheral blood mononu..
Jul 22
Mousaviasl et al., Disease and Diagnosis, doi:10.34172/ddj.500 The Effect of a Low Dose of Vitamin C in Patients With COVID-19: A Double-Blind Randomized Controlled Trial
20% lower mortality (p=0.64), 200% higher ventilation (p=1), and 33% higher ICU admission (p=0.79). RCT 401 hospitalized COVID-19 patients showing no significant differences with low-dose oral vitamin C (1000mg daily for 5 days).
Jul 15
Graydon et al., Current Research in Immunology, doi:10.1016/j.crimmu.2023.100064 High baseline frequencies of natural killer cells are associated with asymptomatic SARS-CoV-2 infection
Analysis of 88 COVID+ patients in the USA showing that a higher frequency of natural killer (NK) cells was associated with asymptomatic infection. Improved NK cell numbers and functioning has been shown for exercise [Oh], better sleep [Ir..
Jul 12
Porter et al., medRxiv, doi:10.1101/2023.07.06.23292300 The ratio between SARS-CoV-2 RNA viral load and culturable viral titer differs depending on stage of infection
Analysis of viral load and infectious virus, showing that the ratio between viral load (measured by PCR) and infectious virus (measured by viral culture) changes dramatically over the course of infection. Early in infection, viral load is..
Jun 28
Rana et al., Biological and Clinical Sciences Research Journal, doi:10.54112/bcsrj.v2023i1.343 Effects of mega dose vitamin C in critically ill COVID-19 patients: a randomized control trial
55% lower mortality (p=0.2), 44% lower ventilation (p=0.41), and 37% shorter hospitalization (p=0.91). RCT 278 COVID-19 ICU patients in Pakistan, showing lower mortality and ventilation, and shorter length of stay with high dose vitamin C treatment, without statistical significance. 30 grams IV vitamin C for four days.
Jun 20
Mahjoub et al., Explore, doi:10.1016/j.explore.2023.06.009 Melatonin, vitamins and minerals supplements for the treatment of Covid-19 and Covid-like illness: a prospective, randomized, double-blind multicenter study.
67% improved recovery (p=0.32). RCT 164 low-risk (no hospitalizations) patients in Tunisia, showing improved recovery with zinc, melatonin, and vitamins A-E. This study includes COVID-19 and COVID-like illness, with 49% of 128 patients receiving a PCR test being COVID-1..
Jun 14
Orellana-Manzano et al., Frontiers in Pharmacology, doi:10.3389/fphar.2023.1197973 A report on SARS-CoV-2 first wave in Ecuador: drug consumption dynamics
Retrospective 10,175 people PCR tested in Ecuador, showing lower risk of PCR+ with multivitamin use and suggesting higher risk with acetaminophen use. The study analyzed drug consumption for COVID-19 symptoms during the 14 days before the..
Jun 1
Liu et al., NCT05694975 Clinical Efficacy of Megadose Vitamin C in Severe and Critical Ill COVID-19 Patients (CEMVISCC): A Multicenter, Randomized, Single-blind, Placebo-controlled Clinical Trial
Estimated 608 patient vitamin C late treatment RCT with results not reported over 1 year after estimated completion.
May 21
Chen et al., Nutrition, doi:10.1016/j.nut.2023.112087 Early oral nutritional supplement improves COVID-19 outcomes among hospitalized older patients during the omicron wave
PSM retrospective 1,181 COVID-19 patients ≥60 years old in China, showing significantly lower mortality with a nutritional supplement. Hospitalization time and viral clearance time was improved with earlier initiation of treatment. The su..
May 11
Kyagambiddwa et al., Infection and Drug Resistance, doi:10.2147/idr.s405256 Thirty-Day Outcomes of Young and Middle-Aged Adults Admitted with Severe COVID-19 in Uganda: A Retrospective Cohort Study
50% lower mortality (p=0.06). Retrospective 246 severe COVID-19 patients in Uganda, showing lower mortality with vitamin C treatment, without statistical significance (p = 0.06).
May 11
Vaisi et al., The Clinical Respiratory Journal, doi:10.1111/crj.13632 The association between nutrients and occurrence of COVID-19 outcomes in the population of Western Iran: A cohort study
38% lower hospitalization (p=0.17) and 10% fewer symptomatic cases (p=0.71). Analysis of nutrient intake and COVID-19 outcomes for 3,996 people in Iran, showing lower risk of COVID-19 hospitalization with sufficient vitamin A, vitamin C, and selenium intake, with statistical significance for vitamin A and selenium.
Apr 28
Pincemail et al., Biomedicines, doi:10.3390/biomedicines11051308 A Pilot Study on Oxidative Stress during the Recovery Phase in Critical COVID-19 Patients in a Rehabilitation Facility: Potential Utility of the PAOT® Technology for Assessing Total Anti-Oxidative Capacity
Analysis of 12 COVID-19 ICU patients showing vitamin C levels significantly below the reference range, and remaining low 2 months after discharge.
Apr 18
Kow et al., Inflammopharmacology, doi:10.1007/s10787-023-01200-5 The effect of vitamin C on the risk of mortality in patients with COVID-19: a systematic review and meta-analysis of randomized controlled trials
47% lower mortality (p=0.03). Meta analysis of 11 vitamin C RCTs showing significantly lower COVID-19 mortality with treatment. The effect size is larger than in our analysis due to the authors' inclusion of 2 trials that we exclude due to combined treatments being li..
Apr 9
Xu et al., Nutrients, doi:10.3390/nu15081848 Association of Oral or Intravenous Vitamin C Supplementation with Mortality: A Systematic Review and Meta-Analysis
Systematic review and meta analysis of vitamin C showing significantly lower mortality for COVID-19 and for sepsis.
Mar 21
Madamombe et al., Pan African Medical Journal, doi:10.11604/pamj.2023.44.142.37858 Factors associated with COVID-19 fatality among patients admitted in Mashonaland West Province, Zimbabwe 2020-2022: a secondary data analysis
53% lower mortality (p=0.0004). Retrospective 672 COVID-19 patients in Zimbabwe, showing lower mortality with vitamin C treatment.
Mar 21
Coskun et al., SiSli Etfal Hastanesi Tip Bulteni / The Medical Bulletin of Sisli Hospital, doi:10.14744/SEMB.2022.66742 The Effect of High-dose Vitamin C Treatment for Acute Respiratory Failure due to Coronavirus Disease Pneumonia on Mortality and Length of Intensive Care Stay: A Retrospective Cohort Study
25% lower mortality (p=0.26), 2% lower ventilation (p=1), no change in ICU admission, and 28% improved recovery (p=0.005). Retrospective 78 ICU patients in Turkey, showing lower mortality with high-dose vitamin C treatment, without statistical significance. The SOFA score was significantly better with treatment at day 4. Authors incorrectly state that "H..
Mar 21
Asoudeh et al., Clinical Nutrition ESPEN, doi:10.1016/j.clnesp.2023.03.013 The association between dietary intakes of zinc, vitamin C and COVID-19 severity and related symptoms: A cross-sectional study
69% lower severe cases (p=0.003). Retrospective 250 recovered COVID-19 patients, showing lower risk of severe cases with higher vitamin C intake.
Mar 15
Schloss et al., Inflammopharmacology, doi:10.1007/s10787-023-01183-3 Nutritional deficiencies that may predispose to long COVID
Review of 22 nutritional factors that have been linked to COVID-19 outcomes, the role of nutrients in COVID-19 infection, and the prevalence of multiple nutritional deficiencies in the population.
Feb 28
Boukef et al., NCT05670444 Melatonin, Vitamins and Minerals Supplements for the Treatment of Covid-19 and Covid-like Illness: Results of a Prospective, Randomised, Double-blinded Multicentre Study
150 patient vitamin C early treatment RCT with results not reported over 1 year after completion.
Feb 13
Yilmaz et al., Acta Biomedica Atenei Parmensis, doi:10.23750/abm.v94i1.13655 Baseline serum vitamin A and vitamin C levels and their association with disease severity in COVID-19 patients
Analysis of 53 consecutive hospitalized COVID-19 patients and 26 matched controls, showing significantly lower vitamin A and vitamin C levels in COVID-19 patients, and a negative correlation between vitamin A and vitamin C levels and CT s..
Feb 3
Yamasaki et al., Microorganisms, doi:10.3390/microorganisms11020397 Pleiotropic Functions of Nitric Oxide Produced by Ascorbate for the Prevention and Mitigation of COVID-19: A Revaluation of Pauling’s Vitamin C Therapy
Extensive review of vitamin C and nitric oxide focusing on the potential antiviral activity of vitamin C for SARS-CoV-2 via the production of nitric oxide. Authors note that vegetables are a major dietary source of nitrate, and that dieta..
Feb 2
Arora et al., Nutrients, doi:10.3390/nu15030771 Global Dietary and Herbal Supplement Use during COVID-19—A Scoping Review
Review of 14 global studies showing that the most frequently used dietary supplements during COVID-19 were vitamin C, vitamin D, zinc, and multivitamins. The most common reason was for improved immune system functioning or reduced COVID-1..
Jan 30
Sallam et al., Journal of Food and Nutrition Research, doi:10.12691/jfnr-11-1-10 Dietary Supplement Use among Children Whose Parents Work at National Research Centre: A Pilot Study
Survey of dietary supplementation showing high usage, and greater use by more highly educated people. The survey covered 200 children whose parents were employees of a research center in Egypt, showing 50% prevalence of supplementation du..
Jan 25
Turobkulovich et al., Emergent: Journal of Educational Discoveries and Lifelong Learning, doi:10.17605/OSF.IO/NSJ6B Applications of quercetin for the prevention of COVID-19 in healthcare workers
73% lower mortality (p=0.11) and 33% fewer symptomatic cases (p=0.03). Prospective study of healthcare workers in Uzbekistan showing lower cases with vitamin C prophylaxis. Very minimal details are provided, there is no baseline information, and control mortality is very high.
Jan 16
Viglione et al., The Gazette of Medical Sciences, doi:10.46766/thegms.pubheal.22120905 Intravenous high dose vitamin C and ozonated saline effective treatment for Covid -19: The Evolution of Local Standard of Care
Retrospective 479 high risk outpatients in the USA treated with a protocol including intravenous vitamin C, vitamin D, zinc, quercetin, bromelain, lactoferrin, HCQ, ivermectin, ozonated saline, azithromycin, ceftriaxone, methylprednisolon..
Jan 13
Đukić et al., Frontiers in Bioscience-Landmark, doi:10.31083/j.fbl2801008 Inhibition of SARS-CoV-2 Mpro with Vitamin C, L-Arginine and a Vitamin C/L-Arginine Combination
In Vitro study showing inhibition of SARS-CoV-2 Mpro with vitamin C, L-arginine, and improved inhibition with the combination of both.
Dec 14
Labbani-Motlagh et al., Journal of Research in Pharmacy Practice, doi:10.4103/jrpp.jrpp_30_22 High-dose intravenous Vitamin C in early stages of severe acute respiratory syndrome coronavirus 2 infection: A double-blind, randomized, controlled clinical trial
33% lower mortality (p=0.74), 13% longer hospitalization (p=0.49), and 16% lower progression (p=0.12). RCT 74 patients in Iran, showing no significant differences in outcomes with high dose vitamin C treatment. Tables 1b and 2a show conflicting baseline SOFA scores. The percentages of patients receiving antiviral treatments and corticoster..
Dec 6
Lamontagne et al., NCT04401150 Lessening Organ Dysfunction With VITamin C - COVID
392 patient vitamin C late treatment RCT with results not reported over 1.5 years after completion. The companion non-COVID trial NCT03680274 has reported results.
Nov 26
Sharif et al., Nutrients, doi:10.3390/nu14235029 Impact of Zinc, Vitamins C and D on Disease Prognosis among Patients with COVID-19 in Bangladesh: A Cross-Sectional Study
46% lower severe cases (p=0.001). Retrospective 962 COVID-19 patients in Bangladesh, showing significantly lower severity with vitamin C, vitamin D, and zinc supplementation, and improved results from the combination of all three.
Nov 23
Tosato et al., Nutrients, doi:10.3390/nu14234984 Effects of l-Arginine Plus Vitamin C Supplementation on Physical Performance, Endothelial Function, and Persistent Fatigue in Adults with Long COVID: A Single-Blind Randomized Controlled Trial
46 patient RCT in Italy showing improved recovery from long COVID symptoms using combined treatment with L-arginine and vitamin C.
Nov 16
Guldemir et al., Work, doi:10.3233/wor-220292 Clinical characteristics of bus drivers and field officers infected with COVID-19: A cross-sectional study from Istanbul
31% lower hospitalization (p=0.05). Retrospective 477 COVID+ public transportation workers in Turkey, showing lower risk of hospitalization with vitamin C use in unadjusted results.
Oct 19
Doocy et al., PLOS Global Public Health, doi:10.1371/journal.pgph.0000924 Clinical progression and outcomes of patients hospitalized with COVID-19 in humanitarian settings: A prospective cohort study in South Sudan and Eastern Democratic Republic of the Congo
63% lower mortality (p=0.22). Prospective study of 144 hospitalized COVID-19 patients in the DRC and South Sudan, showing lower mortality with vitamin C treatment.
Oct 18
Cosentino et al., Journal of Clinical Medicine, doi:10.3390/jcm11206138 Early Outpatient Treatment of COVID-19: A Retrospective Analysis of 392 Cases in Italy
Retrospective 392 outpatients in Italy showing 0.2% mortality with early treatment, compared with >3% in Italy at the time. Treatment varied for individual patients and included HCQ, vitamin D, vitamin C, vitamin A, zinc, quercetin, bromh..
Oct 10
Olczak-Pruc et al., Nutrients, doi:10.3390/nu14194217 Vitamin C Supplementation for the Treatment of COVID-19: A Systematic Review and Meta-Analysis
56% lower mortality (p=0.004). Systematic review and meta analysis of 19 studies showing lower mortality with vitamin C treatment, statistically significant for RCTs but not for non-RCT studies, and longer ICU length of stay.
Sep 22
Özgülteki̇n et al., Kastamonu Medical Journal, doi:10.51271/KMJ-0059 The effect of high-dose vitamin C on renal functions in COVID–19 patients
5% higher mortality (p=1). Retrospective 43 ICU patients in Turkey, 21 treated with vitamin C, showing no significant difference in mortality and increased renal failure. Treatment included stage 1 AKI patients. Vitamin C 45-50 g/day for 5 days.
Sep 19
Mosadegh et al., Microbial Pathogenesis, doi:10.1016/j.micpath.2022.105792 The effect of Nutrition Bio-shield superfood (NBS) on disease severity and laboratory biomarkers in patients with COVID-19: A randomized clinical trial
61% lower mortality (p=0.002) and 28% shorter hospitalization (p=0.001). RCT 70 hospitalized severe COVID-19 patients in Iran, showing lower mortality and improved clinical markers with treatment combining vitamins A, B1–B3, B5, B6, B9, C, D, K, and magnesium, potassium, phosphorus, sulfur, manganese, calcium,..
Sep 2
Foshati et al., Food Science & Nutrition, doi:10.1002/fsn3.3034 Antioxidants and clinical outcomes of patients with coronavirus disease 2019: A systematic review of observational and interventional studies
Systematic review showing that vitamin C, vitamin D, selenium, and zinc can improve COVID-19 clinical outcomes.
Aug 30
Kumar et al., Journal of Family Medicine and Primary Care, doi:10.4103/jfmpc.jfmpc_2437_21 Efficacy of intravenous vitamin C in management of moderate and severe COVID-19: A double blind randomized placebo controlled trial
23% lower mortality (p=0.6) and 21% lower ventilation (p=0.6). RCT 60 ICU patients in India, showing no significant difference in outcomes with vitamin C. Mortality was lower in the vitamin C arm despite having more severe cases at baseline (87% vs. 67%). 1 gram intravenous vitamin C 8 hourly for fou..
Aug 18
Gkioulekas et al., COVID, doi:10.3390/covid2080084 Statistical Analysis Methods Applied to Early Outpatient COVID-19 Treatment Case Series Data
Retrospective analysis of case series data from 3,164 high-risk COVID-19 outpatients treated with early multidrug protocols similar to the McCullough protocol, including hydroxychloroquine, ivermectin, zinc, azithromycin, vitamin C, vitam..
Aug 16
Loucera et al., Virology Journal, doi:10.1186/s12985-023-02195-9 (date from preprint) Real-world evidence with a retrospective cohort of 15,968 COVID-19 hospitalized patients suggests 21 new effective treatments
28% lower mortality (p=0.002). Retrospective 15,968 COVID-19 hospitalized patients in Spain, showing lower mortality with existing use of several medications including metformin, HCQ, azithromycin, aspirin, vitamin D, vitamin C, and budesonide. Since only hospitalized ..
Aug 15
Sinnberg et al., Antioxidants, doi:10.3390/antiox11081580 Vitamin C Deficiency in Blood Samples of COVID-19 Patients
42% lower mortality (p=0.38), 41% lower ventilation (p=0.17), and 61% lower hospitalization (p=0.05). Analysis of 74 COVID-19 patients and 8 controls in Germany, showing low vitamin C levels associated with mortality. There was no significant difference for vitamin A, D, or E levels. Very few group details are provided, for example the ag..
Aug 8
Bhowmik et al., Health Science Reports, doi:10.1002/hsr2.762 Impact of high-dose vitamin C on the mortality, severity, and duration of hospital stay in COVID-19 patients: A meta-analysis
46% lower mortality (p<0.0001). Meta analysis of 15 studies with 2,125 COVID-19 patients showing significantly lower mortality with high-dose vitamin C.
Jul 27
Fogleman et al., The Journal of the American Board of Family Medicine, doi:10.3122/jabfm.2022.04.210529 A Pilot of a Randomized Control Trial of Melatonin and Vitamin C for Mild-to-Moderate COVID-19
4% improved recovery (p=0.83). Early terminated low-risk patient RCT with 32 low-dose vitamin C, 32 melatonin, and 34 placebo patients, showing faster resolution of symptoms with melatonin in spline regression analysis, and no significant difference for vitamin C. All ..
Jul 19
Izzo et al., Pharmacological Research, doi:10.1016/j.phrs.2022.106360 Combining L-Arginine with Vitamin C Improves Long-COVID Symptoms: The Nationwide Multicenter LINCOLN Study
41% improved recovery (p<0.0001). Long COVID trial comparing L-arginine + vitamin C with multivitamin treatment (vitamin B1, B2, B6, B12, nicotinamide, folic acid, pantothenic acid), showing significant improvement in symptoms with L-arginine + vitamin C treatment.
Jul 15
Zuo et al., EMBO reports, doi:10.15252/embr.202256374 (date from preprint) Vitamin C promotes ACE2 degradation and protects against SARS‐CoV‐2 infection
In Vitro and mouse study showing that vitamin C inhibits SARS-CoV-2. Vitamin C lowered ACE2 protein levels in a dose-dependent manner at a concentration of 1-10mM in both cell and humanized ACE2 mouse models.
Jun 16
Ortore et al., International Journal of Translational Medicine, doi:10.3390/ijtm2020022 Evaluation of the Clinical Effects of an Antiviral, Immunostimulant and Antioxidant Phytotherapy in Patients Suffering from COVID-19 Infection: An Observational Pilot Study
Retrospective case series of 240 patients in Italy in 2020, up to 96 years old, showing no mortality and 1.6% hospitalization with early treatment including vitamin C, quercetin, and green tea and red wine polyphenols. The formulation was..
Jun 7
Usanma Koban et al., Bratislava Medical Journal, doi:10.4149/BLL_2022_082 The factors affecting the prolonged PCR positivity in COVID-19 patients
33% improved viral clearance (p=0.73). Retrospective 126 patients in Turkey, showing no significant difference in PCR+ at day 14 with vitamin C treatment.
May 30
Kumar et al., Cureus, doi:10.7759/cureus.25467 Efficacy and Safety of Aspirin, Promethazine, and Micronutrients for Rapid Clinical Recovery in Mild to Moderate COVID-19 Patients: A Randomized Controlled Clinical Trial
89% improved recovery (p=0.05). RCT 260 patients in India, 130 treated with aspirin, promethazine, vitamin C, D, B3, zinc, and selenium, showing faster recovery with treatment. There was no hospitalization, ICU admission, or supplemental oxygen requirements in either gr..
May 27
Galmés et al., Nutrients, doi:10.3390/nu14112254 Suboptimal Consumption of Relevant Immune System Micronutrients Is Associated with a Worse Impact of COVID-19 in Spanish Populations
Ecological study in Spain, showing lower intake of vitamin D, A, B9, and zinc in regions with the highest COVID-19 incidence and mortality. Vitamin D intake was associated with lower prevalence, incidence, and a combined incidence+mortali..
May 19
Hellou et al., Journal of Cellular and Molecular Medicine, doi:10.1111/jcmm.17337 Effect of ArtemiC in patients with COVID-19: A Phase II prospective study
77% improved recovery (p=0.04), 92% lower need for oxygen therapy (p=0.01), 13% shorter hospitalization (p=0.92), and 10% improved viral clearance (p=0.77). RCT 50 hospitalized patients in Israel, 33 treated with curcumin, vitamin C, artemisinin, and frankincense oral spray, showing improved recovery with treatment.
May 18
Yildirim et al., Research Square, doi:10.21203/ Mortality Predictors Of Pre-variant SARS-CoV-2 Infected ARDS Patients Receiving Favipiravir and Tocilizumab
Retrospective 60 ICU patients in Turkey treated with tocilizumab and favipiravir, reporting that there was a higher rate of vitamin C treatment in surviving patients (35% vs 10%; p = 0.03), however the results in the table do not match. T..
May 15
Galindo et al., NCT05029037 High-dose Intravenous Vitamin C (HDIVC) as Adjuvant Therapy in Critical Patients With Positive COVID-19. A Pilot Randomized Controlled Dose-comparison Trial.
Estimated 160 patient vitamin C late treatment RCT with results not reported over 2 years after estimated completion.
May 13
Zangeneh et al., Obesity Medicine, doi:10.1016/j.obmed.2022.100420 Survival analysis based on body mass index in patients with COVID-19 admitted to the intensive care unit of Amir Al-Momenin Hospital in Arak – 2021
4% lower mortality (p=0.86). Retrospective 193 ICU patients in Iran, showing no significant difference with vitamin C treatment.
Apr 20
Pandya et al., Informatics in Medicine Unlocked, doi:10.1016/j.imu.2022.100951 Unravelling Vitamin B12 as a potential inhibitor against SARS-CoV-2: A computational approach
In Silico study showing significant interaction with SARS-CoV-2 targets for multiple vitamins.
Mar 29
Hess et al., Internal and Emergency Medicine, doi:10.1007/s11739-022-02954-6 High-dose intravenous vitamin C decreases rates of mechanical ventilation and cardiac arrest in severe COVID-19
20% lower mortality (p=0.54), 40% lower ventilation (p=0.05), and 27% lower ICU admission (p=0.11). Retrospective 100 severe condition hospitalized patients in the USA, 25 treated with high dose IV vitamin C, showing lower mechanical ventilation and cardiac arrest, and increased length of survival with treatment. 3g IV vitamin C every ..
Mar 19
Coppock et al., Life, doi:10.3390/life12030453 Pharmacologic Ascorbic Acid as Early Therapy for Hospitalized Patients with COVID-19: A Randomized Clinical Trial
50% greater improvement (p=0.16) and 22% higher hospital discharge (p=0.07). RCT with 66 very late stage (8 days from symptom onset) hospitalized patients, 44 treated with vitamin C and 22 control patients, showing no significant differences with treatment.
Mar 11
Salehi et al., Research Square, doi:10.21203/ Risk factors of death in mechanically ventilated COVID-19 patients: a retrospective multi-center study
10% lower mortality (p=0.56). Retrospective 125 mechanically ventilated ICU patients in Iran, showing no significant difference with vitamin C treatment in unadjusted results.
Feb 28
Shehab et al., Tropical Journal of Pharmaceutical Research, doi:10.4314/tjpr.v21i2.13 Immune-boosting effect of natural remedies and supplements on progress of, and recovery from COVID-19 infection
4% lower severe cases (p=1). Retrospective survey-based analysis of 349 COVID-19 patients, showing no significant difference with vitamin C prophylaxis in unadjusted analysis. REC/UG/2020/03.
Feb 28
Nimer et al., Bosnian Journal of Basic Medical Sciences, doi:10.17305/bjbms.2021.7009 The impact of vitamin and mineral supplements usage prior to COVID-19 infection on disease severity and hospitalization
25% lower hospitalization (p=0.08) and 17% lower severe cases (p=0.18). Retrospective 2,148 COVID-19 recovered patients in Jordan, showing lower risk of severity and hospitalization with vitamin C prophylaxis, without statistical significance.
Feb 26
Hajdrik et al., Foods, doi:10.3390/foods11050694 In Vitro Determination of Inhibitory Effects of Humic Substances Complexing Zn and Se on SARS-CoV-2 Virus Replication
In Vitro study of a humic substance containing vitamin C, selemium ions, and zinc ions, showing 50% SARS-CoV-2 inhibition at picomolar concentrations.
Feb 24
Kory et al., Journal of Clinical Medicine Research, doi:10.14740/jocmr4658 “MATH+” Multi-Modal Hospital Treatment Protocol for COVID-19 Infection: Clinical and Scientific Rationale
Review of the data supporting the MATH+ hospital treatment protocol for COVID-19.
Feb 20
Quek et al., Clinical and Translational Medicine, doi:10.1002/ctm2.731 Zinc and vitamin C intake increases spike and neutralising antibody production following SARS‐CoV‐2 infection
Antibody response analysis of 422 SARS-CoV-2 infected men in an RCT showing zinc + vitamin C treatment increased anti-SARS-CoV-2 spike IgG and neutralizing antibody levels compared to other treatments (vitamin C, hydroxychloroquine, iverm..
Feb 11
Gavrielatou et al., Frontiers in Medicine, doi:10.3389/fmed.2022.814587 Effect of Vitamin C on Clinical Outcomes of Critically Ill Patients With COVID-19: An Observational Study and Subsequent Meta-Analysis
58% lower mortality (p=0.11). Retrospective 113 consecutive mechanically ventilated COVID+ ICU patients in Greece, 10 receiving high dose IV vitamin C, showing lower mortality with treatment, without statistical significance (p=0.11). The associated meta analysis incl..
Jan 29
Mohajeri et al., Mediterranean Journal of Nutrition and Metabolism, doi:10.3233/MNM-211521 The difference in the dietary inflammatory index, functional food, and antioxidants intake between COVID -19 patients and healthy persons
Retrospective dietary survey analysis of 500 COVID-19 patients and 500 healthy matched controls in Iran, showing that COVID-19 patients had lower daily consumption of vitamin C, vitamin D, vitamin E, zinc, and selenium. IR.ARUMS.REC.1400...
Jan 21
Goc et al., European Journal of Microbiology and Immunology, doi:10.1556/1886.2021.00022 Inhibitory effects of specific combination of natural compounds against SARS-CoV-2 and its Alpha, Beta, Gamma, Delta, Kappa, and Mu variants
In Vitro study testing combinations of plant extracts and micronutrients with several variants of SARS-CoV-2. A combination of vitamin C, N-acetylcysteine, curcumin, quercetin, resveratrol, theaflavin, naringenin, baicalin, and broccoli e..
Jan 15
Yang et al., Am. J. Transl. Res., 14:1 Traditional Chinese medicine together with high-dose vitamin C improves the therapeutic effect of western medicine against COVID-19
33% faster recovery (p<0.0001) and 36% faster viral clearance (p<0.0001). Prospective study of 60 patients in China with three arms: SOC, SOC+TCM, and SOC+TCM+high dose vitamin C, showing successively faster recovery with the addition of TCM and the addition of high dose vitamin C. TCM included inhaled vitamin ..
Jan 13
Tu et al., Infectious Diseases & Immunity, doi:10.1097/ID9.0000000000000037 Risk Factors for Severity and Mortality in Adult Patients Confirmed with COVID-19 in Sierra Leone: A Retrospective Study
83% lower mortality (p<0.0001). Retrospective 180 hospitalized COVID-19 patients in Sierra Leone, showing lower mortality with vitamin C treatment in unadjusted results.
Jan 3
Hemilä et al., Life, doi:10.3390/life12010062 Bias against Vitamin C in Mainstream Medicine: Examples from Trials of Vitamin C for Infections
Analysis of bias against vitamin C for infections in major studies and editorials.
Dec 28
Baguma et al., Research Square, doi:10.21203/ Characteristics of the COVID-19 patients treated at Gulu Regional Referral Hospital, Northern Uganda: A cross-sectional study
48% higher mortality (p=0.54). Retrospective COVID+ hospitalized patients in Uganda, 385 patients receiving vitamin C treatment, showing higher mortality with treatment, without statistical significance.
Dec 15
Majidi et al., Frontiers in Immunology, doi:10.3389/fimmu.2021.717816 The Effect of Vitamin C on Pathological Parameters and Survival Duration of Critically Ill Coronavirus Disease 2019 Patients: A Randomized Clinical Trial
14% lower mortality (p=0.03). RCT 100 ICU patients in Iran, 31 treated with vitamin C, showing lower mortality with treatment.
Dec 14
Amssayef et al., Cardiovascular & Hematological Disorders-Drug Targets, doi:10.2174/1871529X21666211214153308 Vitamin C inhibits Angiotensin-Converting Enzyme-2 in Isolated Rat Aortic Ring
Ex Vivo study showing vitamin C inhibiting vascular ACE2.
Nov 30
Deschasaux-Tanguy et al., BMC Medicine, doi:10.1186/s12916-021-02168-1 Nutritional risk factors for SARS-CoV-2 infection: a prospective study within the NutriNet-Santé cohort
Analysis of 7,766 adults in France, showing higher intakes of vitamin C, folate, vitamin K, dietary fibre, and fruit and vegetables associated with lower seropositivity.
Nov 30
Xia et al., Nutrition, doi:10.1016/j.nut.2021.111405 High-dose intravenous vitamin C attenuates hyperinflammation in severe coronavirus disease 2019
Retrospective study of 236 hospitalized patients with severe COVID-19 in China. 85 patients received high-dose intravenous vitamin C (HIVC) along with standard care, 151 received standard care alone. Most patients showed signs of hyperinf..
Nov 25
Ried et al., Cureus, doi:10.7759/cureus.19902 Therapies to Prevent Progression of COVID-19, Including Hydroxychloroquine, Azithromycin, Zinc, and Vitamin D3 With or Without Intravenous Vitamin C: An International, Multicenter, Randomized Trial
31% improved recovery (p=0.008). RCT 237 patients in Turkey, 162 treated with IV vitamin C in addition to HCQ/AZ/zinc/vitamin D used for all patients, showing significantly faster recovery with the addition of IV vitamin C. 97% of patients were vitamin D deficient, and l..
Nov 14
Beigmohammadi et al., Trials, doi:10.1186/s13063-021-05795-4 The effect of supplementation with vitamins A, B, C, D, and E on disease severity and inflammatory responses in patients with COVID-19: a randomized clinical trial
89% lower mortality (p=0.11), 41% lower hospitalization (p=0.25), and 45% improved recovery (p=0.001). Small RCT 60 ICU patients in Iran, 30 treated with vitamins A, B, C, D, and E, showing significant improvement in SOFA score and several inflammatory markers at day 7 with treatment. 5,000 IU vitamin A daily, 600,000 IU vitamin D once, 30..
Nov 8
Tehrani et al., Urology Journal, doi:10.22037/uj.v18i.6863 An investigation into the Effects of Intravenous Vitamin C on Pulmonary CT Findings and Clinical Outcomes of Patients with COVID 19 Pneumonia A Randomized Clinical Trial
87% lower mortality (p=0.13) and 18% shorter hospitalization (p=0.23). RCT 54 late stage patients, 18 treated with IV vitamin C (2g every 6h for 5 days), showing significant relative improvements in oxygen saturation and respiratory rate.
Oct 28
Shousha et al., World Journal of Gastroenterology, doi:10.3748/wjg.v27.i40.6951 Hepatic and gastrointestinal disturbances in Egyptian patients infected with coronavirus disease 2019: A multicentre cohort study
94% lower mortality (p=0.003). Retrospective 547 hospitalized COVID+ patients in Egypt, showing lower mortality with vitamin C treatment. Treatment was applied according to the official guidelines, indicating that vitamin C was co-administered with HCQ. Actual treatmen..
Oct 25
Leal-Martínez et al., International Journal of Environmental Research and Public Health, doi:10.3390/ijerph19031172 (date from preprint) Effect of a Nutritional Support System to Increase Survival and Reduce Mortality in Patients with COVID-19 in Stage III and Comorbidities: A Blinded Randomized Controlled Clinical Trial
86% lower mortality (p=0.03) and 57% lower ventilation (p=0.31). 80 patient RCT with 40 patients treated with a comprehensive regimen of nutritional support, showing significantly lower mortality with treatment. Treatment contained cholecalciferol, vitamin C, zinc, spirulina maxima, folic acid, glutami..
Sep 27
Simsek et al., Annals of Medical Research, doi:10.5455/annalsmedres.2020.10.1043 Effects of high dose vitamin C administration in Covid-19 patients
44% lower mortality (p=0.19) and 10% lower ICU admission (p=0.66). Retrospective 139 hospitalized patients in Turkey, 58 treated with high dose vitamin C, showing improved kidney functioning with treatment. Mortality was lower with treatment, but not reaching statistical significance with the small sampl..
Sep 22
Zheng et al., Open Medicine, doi:10.1515/med-2021-0361 No significant benefit of moderate-dose vitamin C on severe COVID-19 cases
157% higher mortality (p=0.33) and 35% worse improvement (p=0.17). Retrospective 397 severe COVID-19 patients in China, showing worse outcomes with vitamin C treatment, without statistical significance. IV vitamin C 2-4g/day. Subject to confounding by indication and immortal time bias. Exclusion criteria..
Sep 7
Xia et al., Aging, doi:10.18632/aging.203503 High-dose vitamin C ameliorates cardiac injury in COVID-19 pandemic: a retrospective cohort study
Retrospective study of 113 severe and critically ill COVID-19 patients with cardiac injury in China. 70 patients had ameliorated cardiac injury (ACI) and 43 had non-ameliorated cardiac injury (NACI) at day 21. 51 patients received high-do..
Sep 1
Sharmin et al., NCT04558424 Randomized, Double -Blind, Placebo Controlled, Trial to Evaluate the Effect of Zinc and Ascorbic Acid Supplementation in COVID-19 Positive Hospitalized Patients in BSMMU
Estimated 50 patient vitamin C late treatment RCT with results not reported over 2 years after estimated completion.
Aug 17
Capone et al., Cureus, doi:10.7759/cureus.9809 Characterization of Critically Ill COVID-19 Patients at a Brooklyn Safety-Net Hospital
Retrospective 102 ICU patients in the USA, 73 receiving vitamin C and zinc, showing a negative correlation of treatment with mortality, but not reaching statistical significance (p = 0.31).
Aug 4
Mohseni et al., Nutrition & Food Science, doi:10.1108/NFS-11-2020-0421 Do body mass index (BMI) and history of nutritional supplementation play a role in the severity of COVID-19? A retrospective study
44% more cases (p=0.002). Retrospective 603 patients in Iran, 34 taking vitamin C supplements, showing increased risk of COVID-19 cases in unadjusted results. IR.SHOUSHTAR.REC.1399.015.
Jul 26
Tan et al., QJM, doi:10.1093/qjmed/hcab184 Efficacy of diammonium glycyrrhizinate combined with vitamin C for treating hospitalized COVID-19 patients: a retrospective, observational stud
25% lower combined mortality/intubation (p=0.74) and 73% lower progression (p=0.002). PSM retrospective 207 hospitalized patients in China, 46 treated with diammonium glycyrrhizinate and vitamin C, showing lower risk of ARDS with treatment.
Jul 9
Rabail et al., Food Science & Nutrition, doi:10.1002/fsn3.2458 Nutritional and lifestyle changes required for minimizing the recovery period in home quarantined COVID-19 patients of Punjab, Pakistan
Survey of 80 recovered COVID-19 patients in Pakistan, showing faster recovery with vitamin C, vitamin D, and zinc supplementation.
Jul 6
Margolin et al., Journal of Evidence-Based Integrative Medicine, doi:10.1177/2515690X211026193 20-Week Study of Clinical Outcomes of Over-the-Counter COVID-19 Prophylaxis and Treatment
94% fewer cases (p=0.003). Retrospective 113 outpatients, 53 (patient choice) treated with zinc, quercetin, vitamin C/D/E, l-lysine, and quina, showing lower cases with treatment. Results are subject to selection bias and limited information on the groups is provid..
Jul 4
Özgünay et al., The European Research Journal, doi:10.18621/eurj.938778 The use of vitamin C in the intensive care unit during the COVID-19 pandemic
9% lower mortality (p=0.69) and 1% higher ventilation (p=1). Retrospective 160 ICU patients, 32 with raised neutrophil/lymphocyte ratio treated with vitamin C, showing no significant differences.
Jun 30
Vishnuram et al., Indian Journal of Basic and Applied Medical Research, doi:10.36848/IJBAMR/2020/29215.55599 Role of high dose oral liposomal vitamin C in reducing mortality in patients with COVID-19
54% lower mortality (p=0.03). Retrospective 8,634 hospitalized patients in India, showing lower mortality with high-dose vitamin C in unadjusted results. No group details are provided, the text and table appear to show different results, and some numbers do not match.
Jun 8
Li et al., Journal of Pharmacy Practice, doi:10.1177/08971900211015052 Use of Intravenous Vitamin C in Critically Ill Patients With COVID-19 Infection
11% higher mortality (p=1). PSM retrospective 8 ICU patients treated with vitamin C and 24 matched controls, showing no significant difference. Authors note that "it is possible for the delayed timing of IV vitamin C to have blunted the beneficial effects as th..
Jun 1
May et al., British Journal of Pharmacology, doi:10.1111/bph.15579 Therapeutic potential of megadose vitamin C to reverse organ dysfunction in sepsis and COVID-19
Review of data supporting the use of megadose vitamin C as a treatment for sepsis and COVID-19.
May 26
Pourhoseingholi et al., Research Square, doi:10.21203/ Case Characteristics, Clinical Data, And Outcomes of Hospitalized COVID-19 Patients In Qom Province, Iran: A Prospective Cohort Study
13% lower mortality (p=0.38). Prospective study of 2,468 hospitalized COVID-19 patients in Iran, showing no significant difference with vitamin C treatment. IR.MUQ.REC.1399.013.
May 11
Aldwihi et al., International Journal of Environmental Research and Public Health, doi:10.3390/ijerph18105086 Patients’ Behavior Regarding Dietary or Herbal Supplements before and during COVID-19 in Saudi Arabia
36% lower hospitalization (p=0.006). Retrospective survey-based analysis of 738 COVID-19 patients in Saudi Arabia, showing lower hospitalization with vitamin C, turmeric, zinc, and nigella sativa, and higher hospitalization with vitamin D. For vitamin D, most patients contin..
May 11
Suna et al., Med. Clin. (Barc.), doi:10.1016/j.medcli.2021.04.010 Effect of high-dose intravenous vitamin C on prognosis in patients with SARS-CoV-2 pneumonia
21% lower mortality (p=0.52) and 2% higher ICU admission (p=1). Retrospective 323 hospitalized patients, 153 treated with vitamin C, showing no significant differences. Patients in each group were in different time periods, with the vitamin C group first. Time based confounding is possible due to impr..
May 3
Malla et al., bioRxiv, doi:10.1101/2021.05.02.442358 Vitamin C inhibits SARS coronavirus-2 main protease essential for viral replication
In SIlico and In Vitro study showing that vitamin C inhibits SARS-CoV-2 3CLpro. Authors note that the different clinical results may be explained in part by the widely varying dosages used, and they conclude that vitamin C and/or derivati..
Apr 30
Elhadi et al., PLOS ONE, doi:10.1371/journal.pone.0251085 Epidemiology, outcomes, and utilization of intensive care unit resources for critically ill COVID-19 patients in Libya: A prospective multi-center cohort study
12% higher mortality (p=0.15). Prospective study of 465 COVID-19 ICU patients in Libya showing no significant differences with treatment.
Apr 22
Zhao et al., Frontiers in Pharmacology, doi:10.3389/fphar.2021.638556 High Dose Intravenous Vitamin C for Preventing The Disease Aggravation of Moderate COVID-19 Pneumonia. A Retrospective Propensity Matched Before-After Study
72% lower progression (p=0.03) and 8% slower viral clearance (p=0.79). PSM retrospective 110 patients, 55 treated with high-dose IV vitamin C, showing lower progression to severe disease with treatment. Patients in each group were in different time periods, time based confounding is likely due to SOC improvi..
Apr 14
Hakamifard et al., Immunopathologia Persa, doi:10.34172/ipp.2022.08 The effect of vitamin E and vitamin C in patients with COVID-19 pneumonia; a randomized controlled clinical trial
46% lower ICU admission (p=0.46) and 1% shorter hospitalization (p=0.82). RCT with 38 patients treated with vitamin C and vitamin E, and 34 control patients, showing lower ICU admission with treatment, but not statistically significant.
Apr 8
Abdulateef et al., Open Medicine, doi:10.1515/med-2021-0273 COVID-19 severity in relation to sociodemographics and vitamin D use
19% lower hospitalization (p=0.69). Survey of 428 recovered COVID-19 patients in Iraq, showing fewer hospital visits for patients on prophylactic vitamin C or D. Hospitalization was lower for those on vitamin C, D, or zinc, without statistical significance.
Apr 8
Gadhiya et al., BMJ Open, doi:10.1136/bmjopen-2020-042549 Clinical characteristics of hospitalised patients with COVID-19 and the impact on mortality: a single-network, retrospective cohort study from Pennsylvania state
1% higher mortality (p=0.99). Retrospective 283 patients in the USA showing higher mortality with all treatments (not statistically significant). Confounding by indication is likely. In the supplementary appendix, authors note that the treatments were usually given fo..
Apr 7
Mulhem et al., BMJ Open, doi:10.1136/bmjopen-2020-042042 3219 hospitalised patients with COVID-19 in Southeast Michigan: a retrospective case cohort study
32% higher mortality (p=0.01). Retrospective database analysis of 3,219 hospitalized patients in the USA. Very different results in the time period analysis (Table S2), and results significantly different to other studies for the same medications (e.g., heparin OR 3.06..
Apr 2
Al Sulaiman et al., Research Square, doi:10.21203/ Ascorbic Acid as an Adjunctive Therapy in Critically Ill Patients with COVID-19: A Multicenter Propensity Score Matched Study
15% lower mortality (p=0.27). Retrospective 158 critically ill patients receiving vitamin C and propensity matched controls, showing mortality OR 0.77 [0.48-1.23], and statistically significantly lower thrombosis, OR 0.42 [0.18-0.94]. 1000mg of vitamin C was given dai..
Mar 30
Holt et al., Thorax, doi:10.1136/thoraxjnl-2021-217487 Risk factors for developing COVID-19: a population-based longitudinal study (COVIDENCE UK)
3% more cases (p=0.86). Prospective survey-based study with 15,227 people in the UK, showing lower risk of COVID-19 cases with vitamin A, vitamin D, zinc, selenium, probiotics, and inhaled corticosteroids; and higher risk with metformin and vitamin C. Statistica..
Mar 8
Hamidi-Alamdari et al., Clinical and Translational Investigation, doi:10.24875/RIC.21000028 Methylene blue for treatment of hospitalized COVID-19 patients: a randomized, controlled, open-label clinical trial, phase 2
44% lower mortality (p=0.38) and 38% shorter hospitalization (p=0.004). RCT 80 hospitalized patients with severe COVID-19, 40 treated with methylene blue + vitamin C + N-acetylcysteine, showing lower mortality, shorter hospitalization, and significantly improved SpO2 and respiratory distress with treatment.
Mar 2
Hemilä et al., Research Square, doi:10.21203/ Vitamin C may increase the recovery rate of outpatient cases of SARS-CoV-2 infection by 70%: reanalysis of the COVID A to Z Randomized Clinical Trial
Reanalysis of Thomas et al. showing that vitamin C increased the recovery rate by 70%, p = 0.025.
Feb 28
Bejan et al., Clinical Pharmacology & Therapeutics, doi:10.1002/cpt.2376 (date from preprint) DrugWAS: Drug‐wide Association Studies for COVID‐19 Drug Repurposing
34% lower mortality (p=0.33), 25% lower ventilation (p=0.47), 15% lower ICU admission (p=0.65), and no change in hospitalization (p=1). Retrospective 9,748 COVID-19 patients in the USA showing lower risk of mortality, ventilation, and ICU admission with vitamin C prophylaxis, without statistical significance.
Feb 26
Gao et al., Aging, doi:10.18632/aging.202557 The efficiency and safety of high-dose vitamin C in patients with COVID-19: a retrospective cohort study
86% lower mortality (p=0.04). Retrospective 76 COVID-19 patients, 46 treated with intravenous high-dose vitamin C, showing lower mortality and improved oxygen requirements with treatment. Dosage was 6g intravenous infusion per 12hr on the first day, and 6g once for th..
Feb 15
Mahto et al., American Journal of Blood Research, 11:1 Seroprevalence of IgG against SARS-CoV-2 and its determinants among healthcare workers of a COVID-19 dedicated hospital of India
26% higher IgG positivity (p=0.49). Retrospective 689 healthcare workers in India, showing no significant difference in IgG positivity with vitamin C prophylaxis.
Feb 12
Thomas et al., JAMA Network Open, doi:10.1001/jamanetworkopen.2021.0369 Effect of High-Dose Zinc and Ascorbic Acid Supplementation vs Usual Care on Symptom Length and Reduction Among Ambulatory Patients With SARS-CoV-2 Infection: The COVID A to Z Randomized Clinical Trial
18% faster recovery (p=0.15). Small 214 low-risk outpatient RCT showing non-statistically significant faster recovery with zinc and with vitamin C. A secondary analysis concludes that vitamin C increases recovery rate by 71% (p = 0.036) []. See also..
Feb 9
Hancock et al., SSRN, doi:10.2139/ssrn.3779211 Case Cluster of RT-PCR COVID-19 Positive Patients with an Unexpected Benign Clinical Course With Vitamin D, Melatonin, Vitamin C, and Viscum Album
Case series of 24 COVID-19 patients (12 confirmed PCR+) treated with vitamin D, vitamin C, and melatonin, showing positive outcomes with no patient having worse than a mild case, including 7 high risk patients.
Feb 1
Muhammad et al., SAGE Open Medicine, doi:10.1177/2050312121991246 Deficiency of antioxidants and increased oxidative stress in COVID-19 patients: A cross-sectional comparative study in Jigawa, Northwestern Nigeria
Case control study with 50 symptomatic COVID-19 patients and 21 healthy controls in Nigeria, showing that COVID-19 patients had significantly lower levels of selenium and zinc, and vitamins A, C, and E. Control patients were younger than ..
Feb 1
Zhao et al., Ann. Palliat. Med., doi:10.21037/apm-20-1387 Beneficial aspects of high dose intravenous vitamin C on patients with COVID-19 pneumonia in severe condition: a retrospective case series study
Retrospective case study of 12 severe/critical COVID-19 patients finding that high dose IV vitamin C improved inflammatory response, immune and organ function. There was no control group.
Jan 31
He et al., NCT04664010 Efficacy and Safety of High-dose Vitamin C Combined With Traditional Chinese Medicine in the Treatment of Moderate and Severe Coronavirus Pneumonia (COVID-19)
60 patient vitamin C late treatment RCT with results not reported over 3 years after completion.
Jan 27
Xing et al., Journal of Pharmaceutical and Biomedical Analysis, doi:10.1016/j.jpba.2021.113927 Vitamin C supplementation is necessary for patients with coronavirus disease: An ultra-high-performance liquid chromatography-tandem mass spectrometry finding
Prospective study with 31 COVID-19 patients and 60 controls reporting on a new method to assess plasma vitamin C concentrations. Vitamin C was deficient (11.4µmol/l vs. 52µmol/l for healthy controls), and returned to a normal range (76µmo..
Jan 19
Abioye et al., BMJ Global Health, doi:10.1136/bmjgh-2020-003176 Effect of micronutrient supplements on influenza and other respiratory tract infections among adults: a systematic review and meta-analysis
Systematic review and meta-analysis of 80 randomized controlled trials showing reduced risk of acute respiratory infections with vitamin C and vitamin D, and shorter duration of symptoms with vitamin C, vitamin D, and zinc.
Jan 18
Hemilä et al., Frontiers in Medicine, doi:10.3389/fmed.2020.559811 Vitamin C and COVID-19
Review of the use of vitamin C for infections and the potential benefit for COVID-19.
Jan 9
JamaliMoghadamSiahkali et al., Research Square, doi:10.21203/ Safety and Effectiveness of High-Dose Vitamin C in Patients with COVID-19; A Randomized Controlled open-label Clinical Trial
25% higher ventilation (p=1) and 31% longer hospitalization (p=0.03). Small late stage RCT for the addition of vitamin C to HCQ and lopinavir/ritonavir, with 30 treatment and 30 control patients, finding a significant reduction in temperature and a significant improvement in oxygenation after 3 days in the ..
Dec 23
Su et al., BioScience Trends, doi:10.5582/bst.2020.03340 Efficacy of early hydroxychloroquine treatment in preventing COVID-19 pneumonia aggravation, the experience from Shanghai, China
135% higher progression (p=0.18) and 34% slower improvement (p=0.04). Retrospective 616 patients in China showing increased risk of disease progression with vitamin C treatment.
Dec 16
Jang et al., Heart & Lung, doi:10.1016/j.hrtlng.2020.10.010 Clinical course of COVID-19 patients treated with ECMO: A multicenter study in Daegu, South Korea
51% improved recovery (p=0.15). Retrospective 19 COVID-19 ECMO patients in South Korea, showing a higher rate of weaning from ECMO with vitamin C treatment, without statistical significance. Authors perform multivariate analysis but do not provide full results, only rep..
Dec 15
Darban et al., Journal of Cellular & Molecular Anesthesia, doi:10.22037/jcma.v6i2.32182 Efficacy of High Dose Vitamin C, Melatonin and Zinc in Iranian Patients with Acute Respiratory Syndrome due to Coronavirus Infection: A Pilot Randomized Trial
33% lower progression (p=1) and 6% shorter ICU admission (p=0.3). Small RCT in Iran with 20 ICU patients, 10 treated with high-dose vitamin C, melatonin, and zinc, not showing significant differences.
Dec 10
Rosenthal et al., JAMA Network Open, doi:10.1001/jamanetworkopen.2020.29058 Risk Factors Associated With In-Hospital Mortality in a US National Sample of Patients With COVID-19
11% lower mortality (p=0.005). Retrospective database analysis of 64,781 hospitalized patients in the USA, showing lower mortality with vitamin C or vitamin D (authors do not distinguish between the two), and higher mortality with zinc and HCQ, statistically significan..
Dec 7
Holford et al., Nutrients, doi:10.3390/nu12123760 Vitamin C—An Adjunctive Therapy for Respiratory Infection, Sepsis and COVID-19
Review of vitamin C use for respiratory infections including COVID-19 and the mechanisms of action. Authors note that evidence to date indicates oral vitamin C (2–8 g/day) may reduce the incidence and duration of respiratory infections, a..
Nov 30
Kumari et al., Cureus 12(11): e11779, doi:10.7759/cureus.11779 The Role of Vitamin C as Adjuvant Therapy in COVID-19
36% lower mortality (p=0.45), 20% lower ventilation (p=0.67), 26% faster recovery (p=0.0001), and 24% shorter hospitalization (p=0.0001). RCT 150 hospitalized patients in Pakistan showing 26% faster recovery, p < 0.0001. 36% lower mortality, not statistically significant due to the small number of events. Dosage was 50 mg/kg/day of intravenous vitamin C.
Nov 30
Louca et al., BMJ Nutrition, Prevention & Health, doi:10.1136/bmjnph-2021-000250 (date from preprint) Modest effects of dietary supplements during the COVID-19 pandemic: insights from 445 850 users of the COVID-19 Symptom Study app
no change in cases (p=1). Survey analysis of dietary supplements showing no significant difference in PCR+ cases with vitamin C usage in the UK, however significant reductions were found in the US and Sweden. These results are for PCR+ cases only, they do not refl..
Nov 3
Behera et al., PLoS ONE, doi:10.1371/journal.pone.0247163 (date from preprint) Role of ivermectin in the prevention of SARS-CoV-2 infection among healthcare workers in India: A matched case-control study
18% fewer cases (p=0.58). Retrospective matched case-control prophylaxis study for HCQ, ivermectin, and vitamin C with 372 healthcare workers, showing lower COVID-19 incidence for all treatments, with statistical significance reached for ivermectin. HCQ OR 0.56, p..
Oct 1
Patel et al., Chest Infections, doi:10.1016/j.chest.2020.08.322 The significance of oral ascorbic acid in patients with COVID-19
29% lower mortality (p=0.18). Retrospective 176 hospitalized patients, 96 treated with oral vitamin C (from 500mg to 1500mg daily), showing lower mortality with treatment.
Sep 20
Yüksel et al., Intensive Care Medicine Experimental, 9:S1, 001458, doi:10.1186/s40635-021-00413-8 Effects of high dose vitamin c on patient outcomes in ARDS patients admitted to intensive care with COVID-19; multi-center retrospective study
19% lower mortality (p=0.04). PSM retrospective 86 ICU patients on mechanical ventilation in Turkey, showing lower mortality with high dose vitamin C treatment (≥200mg/kg for 4 days).
Sep 8
Arvinte et al., Med. Drug Discov, doi:10.1016/j.medidd.2020.100064 Serum Levels of Vitamin C and Vitamin D in a Cohort of Critically Ill COVID-19 Patients of a North American Community Hospital Intensive Care Unit in May 2020: A Pilot Study
Pilot study with 21 ICU patients finding low serum levels of vitamin C and vitamin D in most patients. Older age and low vitamin C level appeared to be co-dependent risk factors for mortality.
Sep 8
Galmés et al., Nutrients, doi:10.3390/nu12092738 Current State of Evidence: Influence of Nutritional and Nutrigenetic Factors on Immunity in the COVID-19 Pandemic Framework
Ecological study of European countries analyzing 10 vitamins and minerals endorsed by the European Food Safety Authority as having sufficient evidence for a causal relationship between intake and optimal immune system function: vitamins D..
Aug 26
Chiscano-Camón et al., Critical Care, doi:10.1186/s13054-020-03249-y Vitamin C levels in patients with SARS-CoV-2-associated acute respiratory distress syndrome
Small study of 18 COVID-19 ARDS patients showing that vitamin C levels were very low - 17 patients had undetectable levels and one had a low level (2.4 mg/L).
Aug 10
Zhang et al., Annals of Intensive Care, doi:10.1186/s13613-020-00792-3 Pilot Trial of High-dose vitamin C in critically ill COVID-19 patients (preprint 8/10/2020)
50% lower mortality (p=0.2). Small RCT for high dose vitamin C for ICU patients showing reduced (but not statistically significant) mortality. Dosage was 12g of vitamin C/50ml every 12 hours for 7 days at a rate of 12ml/hour.
Aug 1
Hiedra et al., Expert Review of Anti-infective Therapy, doi:10.1080/14787210.2020.1794819 The use of IV vitamin C for patients with COVID-19: a case series
Case study of 17 patients receiving IV vitamin C for COVID-19, finding a significant decrease in inflammatory markers, including ferritin and D-dimer, and a trend to decreasing FiO2 requirements, after vitamin C administration. There was ..
Jul 25
Feyaerts et al., Nutrition, doi:10.1016/j.nut.2020.110948 Vitamin C as prophylaxis and adjunctive medical treatment for COVID-19?
Review concluding that there is clear evidence that vitamin C in high doses can reduce interleukin-6 and endothelin-1 mediators. Authors suggest a relatively low dose as prophylaxis, and in cases of severe COVID-19, an (intravenous) high-..
Jul 20
Krishnan et al., J Clin Anesth., doi:10.1016/j.jclinane.2020.110005 Clinical comorbidities, characteristics, and outcomes of mechanically ventilated patients in the State of Michigan with SARS-CoV-2 pneumonia
31% lower mortality (p=0.04). Retrospective 152 mechanically ventilated patients in the USA showing unadjusted lower mortality with vitamin C, vitamin D, HCQ, and zinc treatment, statistically significant only for vitamin C.
Jun 19
Biancatelli et al., Frontiers in Immunology, doi:10.3389/fimmu.2020.01451 Quercetin and Vitamin C: An Experimental, Synergistic Therapy for the Prevention and Treatment of SARS-CoV-2 Related Disease (COVID-19)
Review of the evidence for the use of vitamin C and quercetin both for prophylaxis in high-risk populations and for the treatment of COVID-19 patients.
May 27
Kumar et al., VirusDisease, doi:10.1007/s13337-020-00643-6 (date from preprint) In silico virtual screening-based study of nutraceuticals predicts the therapeutic potentials of folic acid and its derivatives against COVID-19
In Silico analysis finding that magnesium ascorbate, a form of Vitamin C, was found to be the top compound among 106 nutraceuticals for binding to Mpro of SARS-CoV-2.
Oct 1
EFSA, EFSA Journal, doi:10.2903/j.efsa.2009.1226 Scientific Opinion on the substantiation of health claims related to vitamin C and protection of DNA, proteins and lipids from oxidative damage (ID 129, 138, 143, 148), antioxidant function of lutein (ID 146), maintenance of vision (ID 141, 142), collagen formation (ID 130, 131, 136, 137, 149), function of the nervous system (ID 133), function of the immune system (ID 134), function of the immune system during and after extreme physical exercise (ID 144), non-haem iron absorption (ID 132, 147), energy-yielding metabolism (ID 135), and relief in case of irritation in the upper respiratory tract (ID 1714, 1715) pursuant to Article 13(1) of Regulation (EC) No 1924/2006
European Food Safety Administration review concluding that there is a causal relationship between the intake of vitamin C and immune system function.
Jul 31
Vojdani et al., Nutrition Research, doi:10.1016/S0271-5317(05)80799-7 In vivo effect of ascorbic acid on enhancement of human natural killer cell activity
Analysis of 20 healthy subjects in the USA showing that vitamin C increases natural killer (NK) cell activity. showed that a lower frequency of natural killer cells was associated with symptomatic COVID-19 infection.
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