Prevention of covid-19 and other acute respiratory infections with cod liver oil supplementation, a low dose vitamin D supplement: quadruple blinded, randomised placebo controlled trial

Rise in Serum 25-Hydroxyvitamin D Levels during the COVID-19 Pandemic

With the emergence of the COVID-19 pandemic, the absence of established evidence-based treatment protocols led healthcare professionals and the public to explore experimental treatments, including high doses of vitamin D supplements. This study aimed to assess changes in serum 25-hydroxyvitamin D levels during the pandemic, employing a retrospective cohort analysis of data from Charleston Area Medical Center (CAMC). The study analyzed serum 25-hydroxyvitamin D levels in a cohort of 35,556 patients treated at CAMC in 2019, a representative pre-pandemic period, to 2021, a representative pandemic period. Our findings revealed a significant increase in mean serum 25-hydroxyvitamin D levels as compared with 2019 (37 ± 21 vs. 31 ± 15 ng/mL, p ≤ 0.001). Additionally, in 2021, there were significantly more patients exhibiting serum levels in the highest quintiles, specifically >100 ng/mL (1.6% vs. 0.2%), 75-100 ng/mL (4.6% vs. 1.2%), and 50-75 ng/mL (16.0% vs. 8.4%), p ≤ 0.001. This upsurge suggests increased intake of vitamin D supplements, potentially fueled by widespread discussions that were taking place largely on the internet regarding the efficacy of vitamin D against COVID-19. Our findings underscore the critical need for evidence-based public health messaging, especially during health crises, to prevent unnecessary health risks and ensure patient safety.

Vitamin D for the Prevention of Disease: An Endocrine Society Clinical Practice Guideline

BACKGROUND

Numerous studies demonstrate associations between serum concentrations of 25-hydroxyvitamin D (25[OH]D) and a variety of common disorders, including musculoskeletal, metabolic, cardiovascular, malignant, autoimmune, and infectious diseases. Although a causal link between serum 25(OH)D concentrations and many disorders has not been clearly established, these associations have led to widespread supplementation with vitamin D and increased laboratory testing for 25(OH)D in the general population. The benefit-risk ratio of this increase in vitamin D use is not clear, and the optimal vitamin D intake and the role of testing for 25(OH)D for disease prevention remain uncertain.

OBJECTIVE

To develop clinical guidelines for the use of vitamin D (cholecalciferol [vitamin D3] or ergocalciferol [vitamin D2]) to lower the risk of disease in individuals without established indications for vitamin D treatment or 25(OH)D testing.

METHODS

A multidisciplinary panel of clinical experts, along with experts in guideline methodology and systematic literature review, identified and prioritized 14 clinically relevant questions related to the use of vitamin D and 25(OH)D testing to lower the risk of disease. The panel prioritized randomized placebo-controlled trials in general populations (without an established indication for vitamin D treatment or 25[OH]D testing), evaluating the effects of empiric vitamin D administration throughout the lifespan, as well as in select conditions (pregnancy and prediabetes). The panel defined "empiric supplementation" as vitamin D intake that (a) exceeds the Dietary Reference Intakes (DRI) and (b) is implemented without testing for 25(OH)D. Systematic reviews queried electronic databases for publications related to these 14 clinical questions. The Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology was used to assess the certainty of evidence and guide recommendations. The approach incorporated perspectives from a patient representative and considered patient values, costs and resources required, acceptability and feasibility, and impact on health equity of the proposed recommendations. The process to develop this clinical guideline did not use a risk assessment framework and was not designed to replace current DRI for vitamin D.

RESULTS

The panel suggests empiric vitamin D supplementation for children and adolescents aged 1 to 18 years to prevent nutritional rickets and because of its potential to lower the risk of respiratory tract infections; for those aged 75 years and older because of its potential to lower the risk of mortality; for those who are pregnant because of its potential to lower the risk of preeclampsia, intra-uterine mortality, preterm birth, small-for-gestational-age birth, and neonatal mortality; and for those with high-risk prediabetes because of its potential to reduce progression to diabetes. Because the vitamin D doses in the included clinical trials varied considerably and many trial participants were allowed to continue their own vitamin D-containing supplements, the optimal doses for empiric vitamin D supplementation remain unclear for the populations considered. For nonpregnant people older than 50 years for whom vitamin D is indicated, the panel suggests supplementation via daily administration of vitamin D, rather than intermittent use of high doses. The panel suggests against empiric vitamin D supplementation above the current DRI to lower the risk of disease in healthy adults younger than 75 years. No clinical trial evidence was found to support routine screening for 25(OH)D in the general population, nor in those with obesity or dark complexion, and there was no clear evidence defining the optimal target level of 25(OH)D required for disease prevention in the populations considered; thus, the panel suggests against routine 25(OH)D testing in all populations considered. The panel judged that, in most situations, empiric vitamin D supplementation is inexpensive, feasible, acceptable to both healthy individuals and health care professionals, and has no negative effect on health equity.

CONCLUSION

The panel suggests empiric vitamin D for those aged 1 to 18 years and adults over 75 years of age, those who are pregnant, and those with high-risk prediabetes. Due to the scarcity of natural food sources rich in vitamin D, empiric supplementation can be achieved through a combination of fortified foods and supplements that contain vitamin D. Based on the absence of supportive clinical trial evidence, the panel suggests against routine 25(OH)D testing in the absence of established indications. These recommendations are not meant to replace the current DRIs for vitamin D, nor do they apply to people with established indications for vitamin D treatment or 25(OH)D testing. Further research is needed to determine optimal 25(OH)D levels for specific health benefits.

A Systematic Review Supporting the Endocrine Society Clinical Practice Guidelines on Vitamin D

CONTEXT

Low vitamin D status is common and is associated with various common medical conditions.

OBJECTIVE

To support the development of the Endocrine Society's Clinical Practice Guideline on Vitamin D for the Prevention of Disease.

METHODS

We searched multiple databases for studies that addressed 14 clinical questions prioritized by the guideline panel. Of the 14 questions, 10 clinical questions assessed the effect of vitamin D vs no vitamin D in the general population throughout the lifespan, during pregnancy, and in adults with prediabetes; 1 question assessed dosing; and 3 questions addressed screening with serum 25-hydroxyvitamin D (25[OH]D). The Grading of Recommendations Assessment, Development and Evaluation approach was used to assess certainty of evidence.

RESULTS

Electronic searches yielded 37 007 citations, from which we included 151 studies. In children and adolescents, low-certainty evidence suggested reduction in respiratory tract infections with empiric vitamin D. There was no significant effect on select outcomes in healthy adults aged 19 to 74 years with variable certainty of evidence. There was a very small reduction in mortality among adults older than 75 years with high certainty of evidence. In pregnant women, low-certainty evidence suggested possible benefit on various maternal, fetal, and neonatal outcomes. In adults with prediabetes, moderate certainty of evidence suggested reduction in the rate of progression to diabetes. Administration of high-dose intermittent vitamin D may increase falls, compared to lower-dose daily dosing. We did not identify trials on the benefits and harms of screening with serum 25(OH)D.

CONCLUSION

The evidence summarized in this systematic review addresses the benefits and harms of vitamin D for the prevention of disease. The guideline panel considered additional information about individuals' and providers' values and preferences and other important decisional and contextual factors to develop clinical recommendations.

Assessing the Potential of an Enzymatically Liberated Salmon Oil to Support Immune Health Recovery from Acute SARS-CoV-2 Infection via Change in the Expression of Cytokine, Chemokine and Interferon-Related Genes

Cytokines, chemokines, and interferons are released in response to viral infection with the ultimate aim of viral clearance. However, in SARS-CoV-2 infection, there is an imbalanced immune response, with raised cytokine levels but only a limited interferon response with inefficient viral clearance. Furthermore, the inflammatory response can be exaggerated, which risks both acute and chronic sequelae. Several observational studies have suggested a reduced risk of progression to severe COVID-19 in subjects with a higher omega-3 index. However, randomized studies of omega-3 supplementation have failed to replicate this benefit. Omega-3 fats provide important anti-inflammatory effects; however, fatty fish contains many other fatty acids that provide health benefits distinct from omega-3. Therefore, the immune health benefit of whole salmon oil (SO) was assessed in adults with mild to moderate COVID-19. Eleven subjects were randomized to best supportive care (BSC) with or without a full spectrum, enzymatically liberated SO, dosed at 4g daily, for twenty-eight days. Nasal swabs were taken to measure the change in gene expression of markers of immune response and showed that the SO provided both broad inflammation-resolving effects and improved interferon response. The results also suggest improved lung barrier function and enhanced immune memory, although the clinical relevance needs to be assessed in longer-duration studies. In conclusion, the salmon oil was well tolerated and provided broad inflammation-resolving effects, indicating a potential to enhance immune health.

Consensus Statement on Vitamin D Status Assessment and Supplementation: Whys, Whens, and Hows

The 6th International Conference, "Controversies in Vitamin D," was convened to discuss controversial topics, such as vitamin D metabolism, assessment, actions, and supplementation. Novel insights into vitamin D mechanisms of action suggest links with conditions that do not depend only on reduced solar exposure or diet intake and that can be detected with distinctive noncanonical vitamin D metabolites. Optimal 25-hydroxyvitamin D (25(OH)D) levels remain debated. Varying recommendations from different societies arise from evaluating different clinical or public health approaches. The lack of assay standardization also poses challenges in interpreting data from available studies, hindering rational data pooling and meta-analyses. Beyond the well-known skeletal features, interest in vitamin D's extraskeletal effects has led to clinical trials on cancer, cardiovascular risk, respiratory effects, autoimmune diseases, diabetes, and mortality. The initial negative results are likely due to enrollment of vitamin D-replete individuals. Subsequent post hoc analyses have suggested, nevertheless, potential benefits in reducing cancer incidence, autoimmune diseases, cardiovascular events, and diabetes. Oral administration of vitamin D is the preferred route. Parenteral administration is reserved for specific clinical situations. Cholecalciferol is favored due to safety and minimal monitoring requirements. Calcifediol may be used in certain conditions, while calcitriol should be limited to specific disorders in which the active metabolite is not readily produced in vivo. Further studies are needed to investigate vitamin D effects in relation to the different recommended 25(OH)D levels and the efficacy of the different supplementary formulations in achieving biochemical and clinical outcomes within the multifaced skeletal and extraskeletal potential effects of vitamin D.

Effectiveness of Vitamin D and Alpha-Lipoic Acid in COVID-19 Infection: A Literature Review

Over three years since the World Health Organization (WHO) declared COVID-19 a pandemic, it is still a global burden. Vaccines against COVID-19, caused by SARS-CoV-2, are available and effective for preventing disease. However, their protective effects are not 100%. Currently, the U.S. Food and Drug Administration (FDA) has only approved a limited number of inpatient treatments for COVID-19, such as remdesivir, baricitinib, and tocilizumab. These medications have indications and contraindications applicable to a select patient population. Finding additional effective therapies that are widely available with limited risk could be vital in optimizing treatment strategies for this viral illness. Some vitamins and supplements have been identified as potential options for managing COVID-19. Vitamin D (VD) deficiency has been associated with respiratory tract infections. Moreover, alpha-lipoic acid (ALA) is a powerful antioxidant and helps reduce inflammatory responses in many pathologic conditions. This review aims to analyze the current evidence regarding the effectiveness of VD and alpha-lipoic acid in COVID-19 infection in both outpatient and hospitalized patients. Relevant randomized controlled trials (RCTs) were identified via the PubMed database from January 1, 2021, to December 31, 2023. Inclusion criteria were as follows: the study design was a randomized controlled trial (RCT), the usage of a constant dose during the intervention period without any additional boluses, and a research ethics committee approved it. Exclusion criteria included a lack of an outcome or apparent intervention, additional boluses, or a single-dose regimen in all the interventional groups. There were 11 studies with a total sample size of 35,717 patients that met the criteria for this review. A total of 10 RCTs examined the efficacy of VD, and one RCT that reviewed the efficacy of ALA was identified. All of the articles investigated the use of VD or ALA during the treatment of COVID-19. The endpoints of each study varied, including length of stay in hospital, viral load, SARS-CoV-2 infection rate, mechanical ventilation, inflammatory markers, clinical symptoms, Sequential Organ Failure Assessment (SOFA) score, and mortality. In 8/10 VD supplementation trials, significant differences were identified between the interventional and placebo groups in the aforementioned parameters. In 2/10 VD supplementation trials, no significant differences were identified. The ALA supplementation RCT found no differences between the interventional and placebo groups in the SOFA score and 30-day all-cause mortality rate. The current literature suggests that VD can potentially reduce the SARS-CoV-2 infection rate, oxygen requirements, inflammatory markers, clinical symptoms, and mortality. Regarding ALA, although there was a suggestion of benefit, it was not statistically significant. Common limitations among the different studies included relatively small sample sizes, different geographical patient locations among studies, and differences in dosages. Trials investigating the effects of higher doses of VD supplementation on SARS-CoV-2 infection should be conducted. More research is needed to define best practices and optimal dosing protocols for the use of VD in COVID-19.

Preventive Vitamin D Supplementation and Risk for COVID-19 Infection: A Systematic Review and Meta-Analysis

Over the past few decades, vitamin D has been found to play a crucial role in bone homeostasis, muscle function, oncogenesis, immune response and metabolism. In the context of the COVID-19 pandemic, numerous researchers have tried to determine the role vitamin D might play in the immune response to the virus. The aim of this systematic review and meta-analysis is to demonstrate that preventive vitamin D supplementation can play a protective role in the incidence of COVID-19, mortality and admission to intensive care units (ICUs). A comprehensive search on the PubMed/MEDLINE, Scopus, Cochrane and Google Scholar databases was performed on 15 May 2023, and two of the authors independently screened the literature. As effect measures, we calculated the Odds Ratios with their corresponding 95% confidence intervals (ICs). The assessment of potential bias and the evaluation of study quality will be conducted independently by two researchers. Sixteen publications were selected for inclusion in the meta-analysis. Our findings indicate that vitamin D supplementation has a protective effect against the incidence of COVID-19 in RCT studies (OR 0.403, 95% IC 0.218, 0.747), in the incidence of COVID-19 in analytical studies (OR = 0.592, 95% IC 0.476-0.736) and in ICU admission (OR 0.317, 95% IC 0.147-0.680). Subsequent analyses were conducted by type of subject treated (patient/healthcare workers) and type of supplementation (vitamin D vs. placebo/no treatment or high dose vs. low dose). Our meta-analysis suggests a definitive and significant association between the protective role of vitamin D and COVID-19 incidence and ICU admission.

Pharmacological evaluation of vitamin D in COVID-19 and long COVID-19: recent studies confirm clinical validation and highlight metformin to improve VDR sensitivity and efficacy

Nearly four years after its first appearance, and having gone from pandemic to endemic, the SARS-CoV-2 remains out of control globally. The purpose of this study was to evaluate the clinical efficacy of vitamin D (VD) in COVID-19 and long COVID-19, explain the discrepancy in clinical outcomes and highlight the potential impact of metformin on VD efficacy in recent articles. Articles from January 2022 to August 2023 were selected for this review. The objective of this study was achieved by reviewing, analyzing, and discussing articles demonstrating (1) the mechanism of action of VD (2) observational or randomized clinical trials (RCTs) that support or not the beneficial clinical effects of VD in COVID-19 or long COVID. (3) genetic and non-genetic reasons for the variation in the effects of VD. Articles were collected from electronic databases such as PubMed, Scopus, MEDLINE, Google Scholar, Egyptian Knowledge Bank, Science Direct, and Cochrane Database of Systematic Reviews. Twenty three studies conducted in vitro or in animal models indicated that VD may act in COVID-19 through protecting the respiratory system by antimicrobial peptide cathelicidins, reducing lung inflammation, regulating innate and adaptive immune functions and up regulation of autophagy gene activity. Our review identified 58 clinical studies that met the criteria. The number of publications supporting a beneficial clinical activity of VD in treating COVID-19 was 49 (86%), including 12 meta-analyses. Although the total patients included in all articles was 14,071,273, patients included in publications supporting a beneficial role of VD in COVID-19 were 14,029,411 (99.7%). Collectively, extensive observational studies indicated a decisive relationship between low VD levels and the severity of COVID-19 and mortality outcomes. Importantly, evidence from intervention studies has demonstrated the effectiveness of VD supplements in treating COVID-19. Furthermore, the results of 4 observational studies supported the beneficial role of VD in alleviating symptoms of long COVID-19 disease. However, eight RCTs and one meta-analysis of RCTs may contain low-grade evidence against a beneficial role of VD in COVID-19. Twenty-five articles have addressed the association between VDR and DBP genetic polymorphisms and treatment failure of VD in COVID-19. Impaired VDR signaling may underlie the variability of VD effects as non-genetic mechanisms. Interestingly, in recent studies, metformin has a beneficial therapeutic role in COVID-19 and long COVID-19, possibly by improving AMPK signaling of the VDR and enhancing the efficacy of the VD. In conclusion, evidence has been significantly strengthened over the past 18 months, with several meta-analyses and RCTs reporting conclusive beneficial effects of VD supplementation against COVID-19 and highlighting metformin to improve VDR sensitivity and efficacy in treating COVID-19 and long COVID-19.

[Lifestyle medication vitamin D. What evidence is available?]

An undersupply of 25-(OH) vitamin D3 (calcifediol) exists in many countries with moderate sunlight, long winters and only moderate fish consumption. Risk groups for vitamin D3 deficiency are older persons over 65 years, geriatric persons in nursing homes, infants and children/adolescents. Therefore, there are also many situations in Germany which justify vitamin D substitution; however, vitamin D3 is currently praised as a "magic bullet" against everything. But what do the data look like? Where can it help and where can it not help?

Age-differential CD13 and interferon expression in airway epithelia affect SARS-CoV-2 infection - Effects of vitamin D

Young age and high vitamin D plasma levels have been associated with lower SARS-CoV-2 infection risk and favourable disease outcomes. This study investigated mechanisms associated with differential responses to SARS-CoV-2 across age groups and effects of vitamin D. Nasal epithelia were collected from healthy children and adults and cultured for four weeks at the air-liquid interface with and without vitamin D. Gene expression and DNA methylation were investigated. Surface protein expression was confirmed by immunofluorescence while vitamin D receptor recruitment to the DNA was analysed through chromatin immunoprecipitation. HEp-2 cells were used for protein co-immunoprecipitation and luciferase reporter assays. Compared to children, airway epithelia from adults show higher viral RNA recovery following infection. This was associated with higher ANPEP/CD13, reduced type I interferon expression, and differential DNA methylation. In cells from adults, exposure to vitamin D reduced TTLL-12 expression, a negative regulator of the interferon response. This was mediated by vitamin D receptor recruitment to TTLL12, where it instructs DNA methylation through DNA methyltransferase 1. This study links age-dependent differential expression of CD13 and type I interferon to variable infection of upper airway epithelia. Furthermore, it provides molecular evidence for vitamin D reducing viral replication by inhibiting TTLL-12.

Dietary fish intake increased the concentration of soluble ACE2 in rats: can fish consumption reduce the risk of COVID-19 infection through interception of SARS-CoV-2 by soluble ACE2?

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) enters the cells after binding to the membrane-bound receptor angiotensin-converting enzyme 2 (ACE2), but this may be prevented through interception by soluble ACE2 (sACE2) or by inhibition of the ACE2 receptor, thus obstructing cell entry and replication. The main objective of this study was to investigate if fish intake affected the concentration of sACE2 in rats. The secondary aim was to evaluate the in vitro ACE2-inhibiting activity of fish proteins. Rats were fed cod muscle as 25 % of dietary protein, and blood was collected after 4 weeks of intervention. Muscle, backbone, skin, head, stomach, stomach content, intestine and swim bladder from haddock, saithe, cod and redfish were hydrolysed with trypsin before ACE2-inhibiting activity was measured in vitro. In vivo data were compared using unpaired Student's t test, and in vitro data were compared using one-way ANOVA followed by the Tukey HSD post hoc test. The mean sACE2 concentration was 47 % higher in rats fed cod when compared with control rats (P 0·034), whereas serum concentrations of angiotensin II and TNF-α were similar between the two experimental groups. Muscle, backbone, skin and head from all four fish species inhibited ACE2 activity in vitro, whereas the remaining fractions had no effect. To conclude, our novel data demonstrate that fish intake increased the sACE2 concentration in rats and that the hydrolysed fish proteins inhibited ACE2 activity in vitro.

COVID-19: An Update on Epidemiology, Prevention and Treatment, September-2023

After a downward trend for more than 12 months, the incidence of COVID-19 has increased in the last months. Although COVID-19 is not as frequent as in the first years of the pandemic, case numbers are still very high, and it causes a significant number of deaths. COVID-19 is not seen with a predictable frequency, at least two times more deadly than the flu, continues as an epidemic, and has not reached the endemic level yet. Currently, the Omicron strains EG.5 and XBB.1.16 are dominant worldwide. Although BA.2.86 and FLip variants, including FL.1.5.1 are not widespread at the moment, both were shown to be highly immune-evasive and require close monitoring. Prevention of COVID-19 relies on vaccinations, surveillance, proper ventilation of enclosed spaces, isolation of patients, and mask usage. Currently, monovalent COVID-19 vaccines, including XBB.1.5 Omicron SARS-CoV-2, are recommended for both primary and booster vaccinations against COVID-19. Monovalent vaccines, including only original SARS-CoV-2 strain, and bivalent vaccines, including original virus plus BA4/5 variant, are no longer recommended against COVID-19. Booster vaccination with XBB.1.5 containing vaccine should be prioritized for patients at high risk for severe COVID-19. Bacillus Calmette-Guérin (BCG) vaccination does not seem to be effective in preventing COVID-19. At the current phase of the pandemic, nirmatrelvir/ritonavir, remdesivir, molnupiravir, sotrovimab (for patients from XBB.1.5 variant dominant settings), and convalescent plasma can be considered for the treatment of high-risk early-stage outpatients with COVID-19, while hospitalized patients with more severe disease can be treated with dexamethasone, anti cytokines including tocilizumab, sarilumab, baricitinib, and tofacitinib and antithrombotic agents including enoxaparin. Remdesivir oral analogues and ensitrelvir fumarate are promising agents for treating acute COVID-19, which are in phase trials now; however, ivermectin, fluvoxamine, and metformin were shown to be ineffective.

Safety Profile of Vitamin D in Italy: An Analysis of Spontaneous Reports of Adverse Reactions Related to Drugs and Food Supplements

Vitamin D (VitD) is largely used in Italy, often inappropriately; thus, an evaluation of its safety is a crucial issue. This study analyses the adverse reactions (ARs) associated with the use of products containing VitD (VitDps) reported to the Italian National Pharmacovigilance and Phytovigilance networks. From March 2002 to August 2022, a total of 643 and 127 reports concerning 903 and 215 ARs were retrieved from Pharmacovigilance and Phytovigilance networks, respectively. Overall, 332 (29.6%) ARs were classified as serious, and the most described ones were hypercalcaemia, renal failure and tachycardia. Serious AR risk was significantly higher for subjects using more than four concomitant products (OR 2.44 [95% CI 1.30-4.60]) and VitD doses higher than 1000 IU/day (OR 2.70 [95% CI 1.30-5.64]). In Italy, there was a modest decrease in AR reporting, despite the slightly increased use of VitD during the COVID-19 pandemic. To the best of our knowledge, this is the first study describing all VitDps-related ARs observed in the Italian general population. Since underreporting is the main limitation of the safety reporting systems, the necessity to continue ARs monitoring, also using real-world data on VitDps prescription, use and outcome patterns is highlighted.

Micronutrients, genetics and COVID-19

PURPOSE OF REVIEW

Marked inter-individual differences in the clinical manifestation of coronavirus disease 2019 (COVID-19) has initiated studies in the field of genetics. This review evaluates recent genetic evidence (predominantly in the last 18 months) related to micronutrients (vitamins and trace elements) and COVID-19.

RECENT FINDINGS

In patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), altered circulating levels of micronutrients may serve as prognostic markers of disease severity. Mendelian randomization (MR) studies did not find significant effect of variable genetically predicted levels of micronutrients on COVID-19 phenotypes, however, recent clinical studies on COVID-19 point out to vitamin D and zinc supplementation as a nutritional strategy to reduce disease severity and mortality. Recent evidence also points to variants in vitamin D receptor ( VDR ) gene, most notably rs2228570 (FokI) "f" allele and rs7975232 (ApaI) "aa" genotype as poor prognostic markers.

SUMMARY

Since several micronutrients were included in the COVID-19 therapy protocols, research in the field of nutrigenetics of micronutrients is in progress. Recent findings from MR studies prioritize genes involved in biological effect, such as the VDR gene, rather than micronutrient status in future research. Emerging evidence on nutrigenetic markers may improve patient stratification and inform nutritional strategies against severe COVID-19.

Nutrients, herbal bioactive derivatives and commensal microbiota as tools to lower the risk of SARS-CoV-2 infection

The SARS-CoV-2 outbreak has infected a vast population across the world, causing more than 664 million cases and 6.7 million deaths by January 2023. Vaccination has been effective in reducing the most critical aftermath of this infection, but some issues are still present regarding re-infection prevention, effectiveness against variants, vaccine hesitancy and worldwide accessibility. Moreover, although several old and new antiviral drugs have been tested, we still lack robust and specific treatment modalities. It appears of utmost importance, facing this continuously growing pandemic, to focus on alternative practices grounded on firm scientific bases. In this article, we aim to outline a rigorous scientific background and propose complementary nutritional tools useful toward containment, and ultimately control, of SARS-CoV-2 infection. In particular, we review the mechanisms of viral entry and discuss the role of polyunsaturated fatty acids derived from α-linolenic acid and other nutrients in preventing the interaction of SARS-CoV-2 with its entry gateways. In a similar way, we analyze in detail the role of herbal-derived pharmacological compounds and specific microbial strains or microbial-derived polypeptides in the prevention of SARS-CoV-2 entry. In addition, we highlight the role of probiotics, nutrients and herbal-derived compounds in stimulating the immunity response.

An investigation of the correlation of vitamin D status and management outcomes in patients with severe COVID-19 at a South African tertiary hospital

Background

Severe COVID-19 has a poor prognosis, and biomarkers may predict disease severity. This study aimed to assess the effect of baseline Vitamin D (VitD) inadequacy on outcome of patients with severe COVID-19 admitted to intensive care unit (ICU) in a tertiary hospital in South Africa.

Methods

Patients with confirmed SARS-CoV-2 were recruited during wave II of the pandemic in Cape Town. Eighty-six patients were included in the study. They were categorized into three groups "VitD deficient, VitD insufficient and VitD sufficient". We combined the VitD deficient with insufficient group to form "VitD inadequate'' group. Cox regression analysis was done to assess the association between VitD status and mortality. Factors with p< 0.05 in adjusted multivariable cox regression were considered statistically significant.

Results

The proportion of VitD inadequacy was 64% (55/86), with significantly higher proportion of hypertension (66%; p 0.012). Kaplan Meir curve showed no significant difference in the probability of survival among the COVID-19 patients admitted in the ICU with or without VitD inadequacy. However, patients with elevated serum creatinine were significantly more at risk of dying (Adjusted Hazard Ratio 1.008 (1.002 - 1.030, p<0.017).

Conclusion

Our study found a high prevalence of VitD inadequacy (combined deficiency and insufficiency) in COVID-19 patients admitted to the ICU. This may indicate a possible risk of severe disease. Whilst there was no statistically significant relationship between VitD status and mortality in this cohort, baseline VitD may be an important prognostic biomarker in COVID-19 patients admitted to the ICU, particularly in those with comorbidities that predispose to VitD deficiency.

Prevention of COVID-19 with oral vitamin D supplemental therapy in essential healthcare teams (PROTECT): protocol for a multicentre, triple-blind, randomised, placebo-controlled trial

INTRODUCTION

In the COVID-19 pandemic, healthcare workers (HCWs) were at high risk of infection due to their exposure to COVID infections. HCWs were the backbone of our healthcare response to this pandemic; every HCW withdrawn or lost due to infection had a substantial impact on our capacity to deliver care. Primary prevention was a key approach to reduce infection. Vitamin D insufficiency is highly prevalent in Canadians and worldwide. Vitamin D supplementation has been shown to significantly decrease the risk of respiratory infections. Whether this risk reduction would apply to COVID-19 infections remained to be determined. This study aimed to determine the impact of high-dose vitamin D supplementation on incidence of laboratory-confirmed COVID-19 infection rate and severity in HCWs working in high COVID incidence areas.

METHODS AND ANALYSIS

PROTECT was a triple-blind, placebo-controlled, parallel-group multicentre trial of vitamin D supplementation in HCWs. Participants were randomly allocated in a 1:1 ratio in variable block size to intervention (one oral loading dose of 100 000 IU vitamin D₃+10 000 IU weekly vitamin D₃) or control (identical placebo loading dose+weekly placebo). The primary outcome was the incidence of laboratory-confirmed COVID-19 infection, documented by RT-qPCR on salivary (or nasopharyngeal) specimens obtained for screening or diagnostic purposes, as well as self-obtained salivary specimens and COVID-19 seroconversion at endpoint. Secondary outcomes included disease severity; duration of COVID-19-related symptoms; COVID-19 seroconversion documented at endpoint; duration of work absenteeism; duration of unemployment support; and adverse health events. The trial was terminated prematurely, due to recruitment difficulty.

ETHICS AND DISSEMINATION

This study involves human participants and was approved by the Research Ethics Board (REB) of the Centre hospitalier universitaire (CHU) Sainte-Justine serving as central committee for participating institutions (#MP-21-2021-3044). Participants provided written informed consent to participate in the study before taking part. Results are being disseminated to the medical community via national/international conferences and publications in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

https://clinicaltrials.gov/ct2/show/NCT04483635.

Practice and knowledge of dietary supplement consumption among Indonesian adults post-delta wave of the COVID-19 pandemic

Background: Increasing dietary supplement (DS) consumption was observed during the COVID-19 pandemic, including during the post-Delta wave period. This study aimed to measure the practice of DS consumption and respondents' knowledge of DS. Methods: An internet-based survey was distributed from October-December 2021 and obtained 541 valid and completed responses. Descriptive analysis was performed to present the practice of DS consumption, including frequency, duration, aim, preferable dosage form etc. Level of knowledge on DS principles, side effects and regulation were also measured. Inferential analyses were conducted to determine the predictors of the respondents' DS practice and level of knowledge. Results: Data from 541 valid responses showed that 77.63% of respondents consumed DS in the last 3 months, with only 59.52% reporting also consuming DS before the COVID-19 pandemic. One half of the respondents had good knowledge about DS; however, some knowledge regarding side effects and possible drug-supplement interaction needed improvement. Their DS consumption practice was affected by their economic status and history of contracting COVID-19. Nevertheless, the level of knowledge was not affected by the sociodemographic factors and DS supplement experience. Conclusions: Taken together, the practice of self-consumption of DS in Indonesia is increasing; hence, knowledge of DS is necessary to avoid detrimental effects that might occur in the future. Increasing access to information on better labelling and educating consumers about DS are important actions to consider.

The Role of Diet and Specific Nutrients during the COVID-19 Pandemic: What Have We Learned over the Last Three Years?

Nutrients and diets have an important impact on our immune system and infection risk and a huge number of papers have been published dealing with various aspects of nutrition in relation to SARS-CoV-2 infection risk or COVID-19 severity. This narrative review aims to give an update on this association and tries to summarize some of the most important findings after three years of pandemic. The analysis of major studies and systematic reviews leads to the conclusion that a healthy plant-based diet reduces the risks for SARS-CoV-2 infection and especially COVID-19 severity. Regarding micronutrients, vitamin D is to the fore, but also zinc, vitamin C and, to some extent, selenium may play a role in COVID-19. Furthermore, omega-3-fatty acids with their anti-inflammatory effects also deserve attention. Therefore, a major aim of societal nutritional efforts in future should be to foster a high quality plant-based diet, which not only exerts beneficial effects on the immune system but also reduces the risk for non-communicable diseases such as type 2 diabetes or obesity which are also primary risk factors for worse COVID-19 outcomes. Another aim should be to focus on a good supply of critical immune-effective nutrients, such as vitamin D and zinc.

COVID-19, the Gut, and Nutritional Implications

PURPOSE OF REVIEW

Our goal is to provide the most recent and accurate scientific evidence available regarding COVID-19's interaction with the human gut and the role of nutrition/nutritional supplementation in the prevention and treatment of the disease.

RECENT FINDINGS

Gastrointestinal symptoms of COVID-19 are common and often persist even after classically defined illness resolution. Nutritional status and content have been shown to impact infection risk and severity. Well-balanced diets are associated with decreased infection risk/severity, and early nutrition is associated with better outcomes in the critically ill. No specific vitamin supplementation regimen has shown consistent benefit for infection treatment or prevention. The impact of COVID-19 extends far past the pulmonary system, and its impact on the gut should not be ignored. For those interested in adopting lifestyle modifications to prevent severe COVID-19 infection/side effects, consideration should be made for adoption of a well-balanced diet (e.g., Mediterranean style), utilization of probiotics, and addressing nutritional/vitamin deficiencies. Future, high-quality research is needed in this arena.

Can vitamin D status influence seroconversion to SARS-COV2 vaccines?

Existing data indicate an association between vitamin D deficiency and increased severity of respiratory distress due to COVID-19 infection, especially in high-risk populations. To date, the effect of vitamin D on immunogenicity to SARS-CoV-2 vaccines has been investigated solely in young healthcare workers in a few studies, yielding conflicting findings, yet highlighting that the response to immunization is inversely related to age. Vitamin D status can potentially influence the antibody titers in people with a previous (or naïve) SARS-CoV-2 infection and vaccination, given its role in immune regulatory functions. From this standpoint, vitamin D supplementation can help reduce the risk of SARS-CoV-2 infection, COVID-19 severity/mortality and rebalance immunological function, particularly in subjects with vigorous T lymphocyte responses to COVID-19. However, more research is needed to establish a correlation between vitamin D status and the generation of protective serological responses to SARS-CoV-2 vaccination.

Vitamin D and COVID-19: Narrative Review after 3 Years of Pandemic

Active vitamin D [1,25(OH)₂D₃-calcitriol] is a secosteroid hormone whose receptor is expressed on all cells of the immune system. Vitamin D has a global anti-inflammatory effect and its role in the management of a SARS-CoV-2 infection has been investigated since the beginning of the COVID-19 pandemic. In this narrative review, the laboratory and clinical results of a vitamin D supplementation have been collected from both open-label and blinded randomized clinical trials. The results are generally in favor of the utility of maintaining the serum concentrations of calcifediol [25(OH)D₃] at around 40 ng/mL and of the absolute usefulness of its supplementation in subjects with deficient serum levels. However, two very recent large-scale studies (one open-label, one placebo-controlled) have called into question the contribution of vitamin D to clinical practice in the era of COVID-19 vaccinations. The precise role of a vitamin D supplementation in the anti-COVID-19 armamentarium requires further investigations in light of the breakthrough which has been achieved with mass vaccinations.