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Vitamin A for COVID-19
13 studies from 99 scientists
22,277 patients in 7 countries
Statistically significant lower risk for recovery and viral clearance.
7 studies from 6 independent teams in 4 countries show statistically significant improvements.
COVID-19 Vitamin A studies. Oct 2023.
0 0.5 1 1.5+ All studies 38% With exclusions 43% Mortality 42% Hospitalization 10% Recovery 37% Cases 44% Viral clearance 44% RCTs 49% RCT mortality 59% Sufficiency 79% Prophylaxis 39% Early 62% Late 33% Favorsvitamin A Favorscontrol
The European Food Safety Authority has found evidence for a causal relationship between the intake of vitamin A and optimal immune system function Galmés, Galmés (B). Recent:
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Oct 3
Covid Analysis Vitamin A for COVID-19: real-time meta analysis of 17 studies (13 treatment studies and 4 sufficiency studies)
Statistically significant lower risk is seen for recovery and viral clearance. 7 studies from 6 independent teams in 4 countries show statistically significant improvements. • Meta analysis using the most serious outcome reported shows..
Jul 21
Mandour et al., The Egyptian Journal of Bronchology, doi:10.1186/s43168-023-00210-9 Evaluation of vitamin A and E deficiency with severity of SARS-COV-2 disease: a case–control study
100% lower ARDS (p=0.001). Case control study with 30 ICU COVID-19 patients, 30 hospitalized non-ICU patients, and 30 matched healthy controls, showing vitamin A levels associated with COVID-19 and severity, with ICU patient levels < hospitalized patients < healthy..
Jun 30
Chung et al., Brain Sciences, doi:10.3390/brainsci13071014 A Pilot Study of Short-Course Oral Vitamin A and Aerosolised Diffuser Olfactory Training for the Treatment of Smell Loss in Long COVID
75% lower PASC (p=0.05). RCT 24 patients with olfactory dysfunction post-COVID-19 in Hong Kong, showing significantly improved recovery with the addition of vitamin A to aerosolised diffuser olfactory training. 25,000IU vitamin A for 14 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..
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
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
17% lower hospitalization (p=0.04) and 11% fewer symptomatic cases (p=0.03). 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.
Mar 31
DiGuilio et al., Experimental Lung Research, doi:10.1080/01902148.2023.2193637 The multiphasic TNF-α-induced compromise of Calu-3 airway epithelial barrier function
In Vitro study showing that TNF-α induced a multiphasic transepithelial leak in Calu-3 cell layers, and that vitamin A and vitamin D (calcitriol) were effective at reducing the barrier compromise caused by TNF-α.
Mar 21
Lahaye et al., Nutrients, doi:10.3390/nu15061516 Minerals and Antioxidant Micronutrients Levels and Clinical Outcome in Older Patients Hospitalized for COVID-19 during the First Wave of the Pandemic
23% lower mortality (p=0.02) and 2% lower severe cases (p=0.4). Retrospective 235 hospitalized COVID-19 patients in France, showing lower vitamin A levels associated with mortality. Results are provided for vitamin A levels as a continuous value.
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..
Oct 21
Li et al., Medicine, doi:10.1097/MD.0000000000031289 Vitamin A in children’s pneumonia for a COVID-19 perspective: A systematic review and meta-analysis of 15 trials
Systematic review and meta analysis of 15 pediatric vitamin A trials for pneumonia, showing improved clinical efficacy and faster resolution of fever, cough, dyspnea, lung rale, and chest x-ray findings. There was no significant differenc..
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
26% lower mortality (p=1). Prospective study of 144 hospitalized COVID-19 patients in the DRC and South Sudan, showing no significant difference with vitamin A treatment in unadjusted results with only 8 patients receiving vitamin A.
Oct 7
Somi et al., Nutrition and Health, doi:10.1177/02601060221129144 Effect of vitamin A supplementation on the outcome severity of COVID-19 in hospitalized patients: A pilot randomized clinical trial
76% slower improvement (p=0.21) and 8% longer hospitalization (p=0.49). RCT 30 hospitalized patients in Iran, showing no significant difference with vitamin A treatment. All patients received HCQ. 50,000 IU/day intramuscular vitamin A for up to 2 weeks.
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,..
Aug 21
Žarković et al., Molecules, doi:10.3390/molecules27165323 The Impact of Severe COVID-19 on Plasma Antioxidants
Retrospective 88 COVID-19 patients and 33 healthy controls, showing significantly lower vitamin A levels in COVID-19 patients vs. healthy controls, and in patients that did not survive vs. survivors. Patient ages were significantly differ..
Aug 18
Rohani et al., Eastern Mediterranean Health Journal, doi:10.26719/emhj.22.064 Evaluation and comparison of the effect of vitamin A supplementation with standard therapies in the treatment of patients with COVID-19
26% lower hospitalization (p=0.63) and 32% improved recovery (p=0.53). RCT 91 vitamin A and 91 control patients in Iran, showing improved recovery with treatment. All patients received HCQ. 25,000IU/day oral vitamin A for 10 days.
Aug 15
Sinnberg et al., Antioxidants, doi:10.3390/antiox11081580 Vitamin C Deficiency in Blood Samples of COVID-19 Patients
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..
Jul 13
Tong et al., mBio, doi:10.1128/mbio.01485-22 A Retinol Derivative Inhibits SARS-CoV-2 Infection by Interrupting Spike-Mediated Cellular Entry
In Vitro study showing all-trans retinoic acid, a vitamin A derivative, has potent antiviral activity against SARS-CoV-2 in both human cell lines and human organoids of the lower respiratory tract.
Jun 30
Chakraborty et al., Computers in Biology and Medicine, doi:10.1016/j.compbiomed.2022.105788 In-silico screening and in-vitro assay show the antiviral effect of Indomethacin against SARS-CoV-2
In Silico study predicting indomethacin and vitamin A can bind critical host and viral proteins for SARS-CoV-2 interaction, and may be able to compensate for gene expressions changes related to SARS-CoV-2.
May 28
RodanSarohan et al., Clinical Nutrition Open Science, doi:10.1016/j.nutos.2022.05.007 Retinol Depletion in COVID-19
Comparison of 27 COVID-19 ICU patients and 23 control patients, showing significantly lower vitamin A levels in COVID-19 patients.
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 10
Vollenberg et al., Nutrients, doi:10.3390/nu14102007 Significantly Reduced Retinol Binding Protein 4 (RBP4) Levels in Critically Ill COVID-19 Patients
Prospective study of 59 hospitalized COVID-19 patients and 20 matched convalescent control patients in Germany, showing significantly lower vitamin A levels in COVID-19 patients.
Apr 30
Voelkle et al., Nutrients, doi:10.3390/nu14091862 Prevalence of Micronutrient Deficiencies in Patients Hospitalized with COVID-19: An Observational Cohort Study
76% lower combined mortality/ICU admission (p=0.004). Prospective study of 57 consecutive hospitalized COVID-19 patients in Switzerland, showing higher risk of mortality/ICU admission with vitamin A, vitamin D, and zinc deficiency, with statistical significance only for vitamin A and zinc. A..
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 10
DiGuilio et al., International Journal of Molecular Sciences, doi:10.3390/ijms23062995 Micronutrient Improvement of Epithelial Barrier Function in Various Disease States: A Case for Adjuvant Therapy
Review of epithelial and endothelial barrier compromise and associated disease risk including COVID-19, and the potential benefits of vitamin A, vitamin D, and zinc for improving barrier function.
Mar 8
Elkazzaz et al., medRxiv, doi:10.1101/2022.03.05.22271959 13 cis retinoic acid improved the outcomes of COVID-19 patients. A randomized clinical trial
86% lower mortality (p=0.23), 67% lower ICU admission (p=0.24), 35% faster recovery (p<0.0001), and 44% faster viral clearance (p<0.0001). RCT with 20 13-cis-retinoic acid patients and 20 control patients, showing faster recovery and viral clearance with treatment. Aerosolized 13-cis-retinoic acid with increasing dose from 0.2 mg/kg/day to 4 mg/kg/day for 14 days, plus oral..
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
21% lower hospitalization (p=0.4) and 21% lower severe cases (p=0.36). Retrospective 2,148 COVID-19 recovered patients in Jordan, showing no significant differences in the risk of severity and hospitalization with vitamin A prophylaxis.
Jan 7
Al-Saleh et al., BioMetals, doi:10.1007/s10534-021-00355-48 Essential metals, vitamins and antioxidant enzyme activities in COVID-19 patients and their potential associations with the disease severity
Prospective study of 155 COVID-19 patients in Saudi Arabia, showing that 37% of patients were vitamin A deficient (< 0.343 mg/L). Patients with severe COVID-19 symptoms had 23% lower vitamin A levels compared to asymptomatic patients afte..
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..
Aug 23
Morita et al., Viruses, doi:10.3390/v13081669 All-Trans Retinoic Acid Exhibits Antiviral Effect against SARS-CoV-2 by Inhibiting 3CLpro Activity
In Vitro and In Silico study showing that all-trans retinoic acid is a potent SARS-CoV-2 3CLpro inhibitor, inhibits SARS-CoV-2 replication in VeroE6/TMPRSS2 cells, and is effective against alpha, beta, gamma, and delta variants in Calu-3 ..
Jun 24
Tepasse et al., Nutrients, doi:10.3390/nu13072173 Vitamin A Plasma Levels in COVID-19 Patients: A Prospective Multicenter Study and Hypothesis
70% lower mortality (p=0.04) and 45% lower progression (p=0.05). Prospective analysis of 40 hospitalized patients and 47 age-matched convalescent patients, showing significantly lower vitamin A levels in critical patients, and significantly lower vitamin A levels in hospitalized patients vs. controls. ..
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)
56% fewer cases (p=0.41). 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..
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
Sarohan et al., medRxiv, doi:10.1101/2021.01.30.21250844 Retinol Depletion in Severe COVID-19
282% higher mortality (p=0.001). Retrospective 27 severe COVID-19 patients and 23 non-COVID-19 patients, showing significantly lower vitamin A levels in COVID-19 patients (0.37mg/L vs. 0.52 mg/L, p<0.001). 10 of 27 COVID-19 patients received vitamin A, with higher mortal..
Jan 31
Al-Sumiadai et al., Systematic Reviews in Pharmacy, 12:1 Therapeutic effect of vitamin A on COVID-19 patients and its prophylactic effect on contacts
67% lower progression (p=0.27) and 38% faster recovery. Treatment and prophylaxis studies of vitamin A in Iraq. The treatment study contained 100 patients, 50 treated with 200,000IU vitamin A for two days, showing lower progression to severe disease, and shorter duration of symptoms. The proph..
Jan 20
Stephensen et al., British Journal of Nutrition, doi:10.1017/S0007114521000246 Vitamin A in resistance to and recovery from infection: relevance to SARS-CoV2
Review of the potential benefits of vitamin A for COVID-19, including maintaining innate and adaptive immunity, minimizing inflammation, supporting repair of respiratory epithelium and preventing fibrosis, and counteracting adverse effect..
Dec 31
Al-Sumiadai et al., EurAsian Journal of Biosciences, 14:7347-7350 Therapeutic effect of Vitamin A on severe COVID-19 patients
86% lower mortality (p=0.002). Retrospective 70 severe condition patients treated with vitamin A (200,000IU for two days), salbutamol, and budesonide, and 70 patients not treated with vitamin A, showing significantly lower mortality with the addition of vitamin A.
Dec 31
Midha et al., Reviews in Medical Virology, doi:10.1002/rmv.2204 Mega doses of retinol: A possible immunomodulation in Covid-19 illness in resource-limited settings
Review of the potential benefits of vitamin A for COVID-19, including the effect of vitamin A on ACE2 expression in the respiratory tract, potentially improving the generation of protective immune responses to vaccines, and dosage and saf..
Oct 26
Tomasa-Irriguible et al., Metabolites, doi:10.3390/metabo11090565 (date from preprint) Low Levels of Few Micronutrients May Impact COVID-19 Disease Progression: An Observational Study on the First Wave
71% lower ventilation (p=0.001) and 61% lower ICU admission (p=0.004). Retrospective 120 hospitalized patients in Spain showing vitamin A deficiency associated with higher ICU admission.
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 15
Li et al., Aging, doi:10.18632/aging.103888 Revealing the targets and mechanisms of vitamin A in the treatment of COVID-19
Bioinformatics and network pharmacology analysis identifying potential mechanisms of action of vitamin A for COVID-19.
Jun 24
Andrade et al., SciELO preprints, doi:10.1590/SciELOPreprints.839 Vitamin A and D deficiencies in the prognosis of respiratory tract infections: A systematic review with perspectives for COVID-19 and a critical analysis on supplementation
Systematic review showing deficiencies of vitamins A and D negatively affecting the prognosis of respiratory tract infections.
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