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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).
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Summary.
Nov 21 |
Vitamin A for COVID-19: real-time meta analysis of 20 studies (14 treatment studies and 6 sufficiency studies) | |
| Statistically significant lower risk is seen for recovery and cases. 7 studies from 6 independent teams in 3 countries show significant improvements. Meta analysis using the most serious outcome reported shows 36% [6‑56%] lower.. | ||
Jun 3 |
et al., Brazilian Journal of Otorhinolaryngology, doi:10.1016/j.bjorl.2024.101451 | Therapeutic effects of olfactory training and systemic vitamin A in patients with COVID-19-related olfactory dysfunction: a double-blinded randomized controlled clinical trial |
| RCT 90 outpatients with post-COVID-19 anosmia showing significant improvements in smell alterations with olfactory training after 3 and 12 months. Adding oral vitamin A to olfactory training resulted in higher rates of improvement, but th.. | ||
Apr 26 |
et al., BMC Pulmonary Medicine, doi:10.1186/s12890-024-03013-w | Retinol and retinol binding protein 4 levels and COVID-19: a Mendelian randomization study |
| Mendelian randomization study suggesting a causal association between retinol and related proteins (RBP4, RDH16, CRABP1) and COVID-19. The study found that genetically-predicted higher retinol levels were associated with lower COVID-19.. | ||
Apr 5 |
et al., Неонатологія, хірургія та перинатальна медицина, doi:10.24061/2413-4260.XIV.1.51.2024.6 | Micronutrient status (vitamins A and D) and its effect on the severity of the course of COVID-19 in children |
| 61% lower severe cases (p=0.14) and 84% fewer cases (p=0.2). Retrospective 112 pediatric COVID-19 patients and 23 healthy controls showing lower levels of vitamins A and D associated with more severe disease. Patients with moderate and severe COVID-19 had significantly lower vitamin A, vitamin D, a.. | ||
Mar 24 |
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 7 |
et al., Journal of Clinical Medicine, doi:10.3390/jcm13061538 | Vitamin A Positively Correlates with Secretory Immunoglobulin A: A Cross-Sectional Study in Omicron COVID-19 Outpatients |
| Analysis of 39 COVID-19 outpatients showing a positive correlation between vitamin A nutritional status and secretory immunoglobulin A (SIgA) levels. Patients with higher dietary vitamin A intake showed higher SIgA/IgG1 and SIgA/IgG3 rati.. | ||
Jan 29 |
et al., Nutrients, doi:10.3390/nu16030385 | Micronutrient Status of Critically Ill Patients with COVID-19 Pneumonia |
| Prospective pilot study of 20 critically ill COVID-19 ICU patients showing high deficiency rates of 50-100% for vitamins A, B6, and D; zinc; and selenium at admission. Deficiencies of vitamins B6 and D, and low iron status, persisted afte.. | ||
Jan 18 |
et al., Viruses, doi:10.3390/v16010140 | Retinoic Acid-Mediated Inhibition of Mouse Coronavirus Replication Is Dependent on IRF3 and CaMKK |
| Mouse study showing inhibition of mouse coronavirus replication with all-trans retinoic acid (RA), a metabolite of vitamin A. Authors find that RA confers protection against infection by activating interferon responses in an IRF3-dependen.. | ||
Jan 3 |
et al., Computers in Biology and Medicine, doi:10.1016/j.compbiomed.2024.107942 | All-trans retinoic acid acts as a dual-purpose inhibitor of SARS-CoV-2 infection and inflammation |
| In Vitro and In Silico study showing that all-trans retinoic acid (an active metabolite of vitamin A) inhibits the entry and replication of SARS-CoV-2 by binding to ACE2 / 3CLpro / RdRp / helicase / 3′-to-5′ exonuclease, and reduces exces.. | ||
Dec 31 2023 |
et al., Journal of Nutritional Science and Vitaminology, doi:10.3177/jnsv.69.395 | Vitamin A Nutritional Status and Clinical Outcomes in COVID-19: A Systematic Review |
| Systematic review of seven observational studies with 608 COVID-19 patients, showing an association between lower vitamin A levels and worse clinical outcomes including longer hospitalization, increased need for intensive care and mechani.. | ||
Nov 15 2023 |
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.. | ||
Oct 4 2023 |
et al., Indian Journal of Pharmaceutical Education and Research, doi:10.5530/ijper.57.4.126 | In Silico Discovering STRA 6 Vitamin A Receptor, as a Novel Binding Receptor of COVID-19 |
| In Silico study analyzing the potential role of the STRA6 vitamin A receptor in SARS-CoV-2 infection. Authors found that the SARS-CoV-2 spike protein binds strongly to STRA6, suggesting potential use in addition to ACE2. Binding to STRA6 .. | ||
Jul 21 2023 |
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 2023 |
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 2023 |
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 2023 |
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 2023 |
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 2023 |
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 2023 |
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 2023 |
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 2022 |
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 2022 |
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 2022 |
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 2022 |
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 2022 |
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 2022 |
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 2022 |
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 2022 |
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 2022 |
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 2022 |
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 2022 |
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 2022 |
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 2022 |
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 2022 |
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 2022 |
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 2022 |
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 2022 |
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 2022 |
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 2021 |
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 2021 |
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 2021 |
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 2021 |
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 2021 |
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 2021 |
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 2021 |
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 2021 |
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 2020 |
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 2020 |
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 2020 |
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 2020 |
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 2020 |
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 2020 |
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. | ||
Oct 1 2009 |
, EFSA Journal, doi:10.2903/j.efsa.2009.1221 | Scientific Opinion on the substantiation of health claims related to vitamin A and cell differentiation (ID 14), function of the immune system (ID 14), maintenance of skin and mucous membranes (ID 15, 17), maintenance of vision (ID 16), maintenance of bone (ID 13, 17), maintenance of teeth (ID 13, 17), maintenance of hair (ID 17), maintenance of nails (ID 17), metabolism of iron (ID 206), and protection of DNA, proteins and lipids from oxidative damage (ID 209) 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 A and immune system function. | ||
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