Nutritional risk of vitamin D, vitamin C, zinc, and selenium deficiency on risk and clinical outcomes of COVID-19: A narrative review

LLL 44-4 : Micronutrients in acute disease and critical illness

Micronutrients (MN), i.e. trace elements and vitamins, are essential components of the diet in relatively small amounts in any form of nutrition, with special needs in critically ill patients. Critical illness is characterised by the presence of inflammation and oxidative stress. MNs are tightly involved in antioxidant and immune defences. In addition, some conditions, and treatments result in large losses of biological fluids containing MNs: therefore, acute renal injury requiring renal replacement therapy, acute intestinal failure, and major burns and trauma are at high risk of acute depletion of body stores, and of deficiency. MN requirements are increased above standard DRI. Blood level interpretation is complicated by inflammation: some biomarkers assist the status determination. Due to the acute challenges of critical illness, it of utmost importance to cover the needs to maintain the organism's endogenous immune and antioxidant defences, and capacity to repair tissues. Practical strategies are proposed.

Peripheral biomarkers as a predictor of poor prognosis in severe cases of COVID-19

We evaluated glycemia and triglyceride, hepatic, muscular, and renal damage markers, redox profile, and leptin and ghrelin hormone levels of COVID-19 patients. We also realized statistical analysis to verify the potential of biomarkers to predict poor prognosis and the correlation between them in severe cases. We assessed glycemia and the levels of triglycerides, hepatic, muscular, and renal markers in automatized biochemical analyzer. The leptin and ghrelin hormones were assessed by the ELISA assay. Severe cases presented high glycemia and triglyceride levels. Hepatic, muscular, and renal biomarkers were altered in severe patients. An oxidative stress status was found in severe COVID-19 patients. Severe cases also had increased levels of leptin. The ROC curves indicated many biomarkers as poor prognosis predictors in severe cases. The Spearman analysis showed that biomarkers correlate between themselves. Patients with COVID-19 showed significant dysregulation in the levels of several peripheral biomarkers. We bring to light that a robust panel of peripheral biomarkers and hormones predict poor prognosis in severe cases of COVID-19, as well as correlates between them. Early monitoring of these biomarkers may conduct the correct clinical intervention associated with the clinical symptoms for treating patients infected by SARS-CoV-2.

Malnutrition, Functional Decline, and Institutionalization in Older Adults after Hospital Discharge Following Community-Acquired Pneumonia

BACKGROUND AND AIMS

Community-acquired pneumonia (CAP) is a major threat to older adults, but mid-term implications are poorly described. The aim was to analyze functional decline, institutionalization, malnutrition, and risk factors after hospital admission for CAP.

METHODS

This prospective observational study included patients over 65 years discharged after CAP between May 2019 and July 2021. We performed a comprehensive geriatric assessment and a general nutritional assessment 30-60 days after CAP. This included the MNA and blood test with trace elements and vitamins. The main outcomes were functional decline, institutionalization, and malnutrition. Multivariate logistic regression was used for the analyses.

RESULTS

In total, 144 patients of 77.15 ± 7.91 years, 55.6% male, and 9% previously institutionalized were analyzed. At hospital admission, the Charlson Comorbidity Index (CCI) was 1.5 ± 1.6, the Pneumonia Severity Index was 98.1 ± 25.9, and the previous Barthel Index (BI) was 93.06 ± 17.13. Hospital stay was 9.72 ± 7.88 days. After 44.6 ± 14.4 days, 48.6% patients showed functional decline and 19.4% were institutionalized. Age (OR 1.17; CI 95% 1.09-1.26), previous institutionalization (29.1; 3.7-224.7), BI (1.09; 1.05-1.14), CCI (1.5; 1.1-2.1), and length of stay (1.1, 1.02-1.18) were independently associated with functional decline. The only predictors of new institutionalization were previous BI (0.96; 0.93-0.99) and length of stay (1.06; 1.00-1.13). The MNA indicated malnutrition in 28% of the community-dwelling patients and 67.9% of those institutionalized, with risk of malnutrition being 45.7% and 9.5%, respectively, after an average of 44.6 days of CAP diagnosis. The predictors of malnutrition were previous institutionalization (10.62; 2.20-51.21), BI (0.95; 0.92-0.98), and length of stay (1.12; 1.04-1.20). Micronutrient deficiencies were mainly zinc (61.8%), vitamin D (54.5%), and vitamin C (45.1%). An MNA score < 17 points or hypoalbuminemia showed good specificity to identify these deficiencies.

CONCLUSIONS

After CAP admission, functional decline, institutionalization, and malnutrition rates were high. Longer hospital stay was a common risk factor for all outcomes. The presence of hypoalbuminemia or an MNA < 17 in older patients should prompt suspicion of deficiencies in micronutrients, such as vitamin D, C, and zinc.

Ascorbic acid modulates immune responses through Jumonji-C domain containing histone demethylases and Ten eleven translocation (TET) methylcytosine dioxygenase

Ascorbic acid is a redox regulator in many physiological processes. Besides its antioxidant activity, many intriguing functions of ascorbic acid in the expression of immunoregulatory genes have been suggested. Ascorbic acid acts as a co-factor for the Fe+2 -containing α-ketoglutarate-dependent Jumonji-C domain-containing histone demethylases (JHDM) and Ten eleven translocation (TET) methylcytosine dioxygenasemediated epigenetic modulation. By influencing JHDM and TET, ascorbic acid facilitates the differentiation of double negative (CD4- CD8- ) T cells to double positive (CD4+ CD8+ ) T cells and of T-helper cells to different effector subsets. Ascorbic acid modulates plasma cell differentiation and promotes early differentiation of hematopoietic stem cells (HSCs) to NK cells. These findings indicate that ascorbic acid plays a significant role in regulating both innate and adaptive immune cells, opening up new research areas in Immunonutrition. Being a water-soluble vitamin and a safe micro-nutrient, ascorbic acid can be used as an adjunct therapy for many disorders of the immune system.

Diet Quality and Risk of SARS-CoV-2 Infection or COVID-19: A Systematic Review of Observational Studies

The COVID-19 pandemic highlighted the importance of healthy diets in the management of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and COVID-19. Evidence suggests the influence of diet and dietary patterns during post-COVID-19, and the impact of the COVID-19 pandemic on dietary habits and quality. However, limited evidence lies on the association between a healthy diet, and risk of SARS-CoV-2 infection or COVID-19. This study aimed to conduct a systematic review of observational studies to examine the association between diet quality, and the risk of SARS-CoV-2 infection or COVID-19 among adult populations. 6158 research articles from Scopus, EMBASE, PubMed, and MEDLINE databases were identified for eligibility. Only observational studies were included. Study quality was assessed using the National Institutes of Health Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. Thirteen studies were included (4 with SARS-CoV-2 infection and 9 with COVID-19 as the outcome); 3 were case-control, 3 were cross-sectional, and 7 were prospective studies. Adherence to Mediterranean diet was examined as exposure in 7 studies, and was associated with decreased risk of SARS-CoV-2 infection in 2 studies, with estimates varying from 12% to 22%, while COVID-19 risk or severity was found to be reduced in 3 studies with odds ratios (ORs) ranging from 36% to 77%. The Dietary Approaches to Stop Hypertension diet was inversely associated with COVID-19 hospitalization (OR: 0.19; 95% CI: 0.07, 0.55), whereas a healthy plant-based diet had an inverse association with both COVID-19 infection (hazard ratio [HR]: 0.91; 95% CI: 0.88, 0.94) and severity (HR: 0.59; 95% CI: 0.47, 0.74). Studies examining individual food groups generally found lower risk of infection or COVID-19 in association with larger dietary intakes of fruits, vegetables, and fiber. The overall findings of the observational studies in this review support the concept that nutritious diets might lower the risk of SARS-CoV-2 infection or COVID-19. This study was registered at PROSPERO as CRD42023397371.

Strategies for the Management of Spike Protein-Related Pathology

In the wake of the COVID-19 crisis, a need has arisen to prevent and treat two related conditions, COVID-19 vaccine injury and long COVID-19, both of which can trace at least part of their aetiology to the spike protein, which can cause harm through several mechanisms. One significant mechanism of harm is vascular, and it is mediated by the spike protein, a common element of the COVID-19 illness, and it is related to receiving a COVID-19 vaccine. Given the significant number of people experiencing these two related conditions, it is imperative to develop treatment protocols, as well as to consider the diversity of people experiencing long COVID-19 and vaccine injury. This review summarizes the known treatment options for long COVID-19 and vaccine injury, their mechanisms, and their evidentiary basis.

Potential of macronutrients and probiotics to boost immunity in patients with SARS-COV-2: a narrative review

Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-COV-2) may cause inflammation and increased cytokine secretion. Dietary factors may play an important role in enhancing the immune responses against infectious diseases such as SARS-COV-2. This narrative review aims to determine the effectiveness of macronutrients and probiotics to improve immunity in SARS-COV-2 patients. Dietary proteins may boost pulmonary function in SARS-COV-2 patients through inhibitory effects on the Angiotensin-converting enzyme (ACE) and reduce Angiotensin (ANG-II). Moreover, omega-3 fatty acids may improve oxygenation, acidosis, and renal function. Dietary fiber may also produce anti-inflammatory effects by reducing the level of high-sensitivity C-Reactive Protein (hs-CRP), Interleukin (IL-6), and Tumor necrosis factor (TNF-α). In addition, some evidence indicates that probiotics significantly improve oxygen saturation which may enhance survival rate. In conclusion, the consumption of a healthy diet including adequate macronutrients and probiotic intake may decrease inflammation and oxidative stress. Following this dietary practice is likely to strengthen the immune system and have beneficial effects against SARS-COV-2.

Hypoglycemia Induced by Zinc Supplementation for COVID-19 Prophylaxis: A Case Series

There has been significant research and therapeutic activity within the healthcare sector in response to the coronavirus disease 2019 (COVID-19). In the United States, a complementary and alternative medicine (CAM) treatment regimen for improving patients' immune systems against COVID-19 prophylaxis includes excess zinc, vitamin C, and vitamin D supplementation administered over a seven-day period. Despite the fact that zinc and other mineral supplements are becoming increasingly popular in Western culture, clinical research on CAM remains limited. This case series examines three patients treated with a surplus of zinc tablets for COVID-19 prophylaxis who presented with moderate-to-severe hypoglycemia. Varying amounts of glucose were administered to these patients to offset their low blood sugar levels. Medical staff noted a positive Whipple's triad in two of the patients but observed no other abnormalities in the laboratory values. All three patients were instructed to cease zinc tablet intake upon discharge. Our findings raise awareness of the potential dangers associated with mineral supplements and serve as a warning for those seeking CAM treatment options.

Effect of an Immune-Boosting, Antioxidant and Anti-Inflammatory Food Supplement in Hospitalized COVID-19 Patients: A Prospective Randomized Pilot Study

Background: COVID-19 disease is a serious global health problem. Few treatments have been shown to reduce mortality and accelerate time to recovery. The aim of this study was to evaluate the potential effect of a food supplement (probiotics, prebiotics, vitamin D, zinc and selenium) in patients admitted with COVID-19. Methods: A prospective randomized non-blinded clinical trial was conducted in a sample of 162 hospitalized patients diagnosed with COVID-19 recruited over eight months. All patients received standard treatment, but the intervention group (n = 67) was given one food supplement stick daily during their admission. After collecting the study variables, a statistical analysis was performed comparing the intervention and control groups and a multivariate analysis controlling for variables that could act as confounding factors. Results: ROC curve analysis with an area under the curve (AUC) value of 0.840 (p < 0.001; 95%CI: 0.741–0.939) of the food supplement administration vs. recovery indicated good predictive ability. Moreover, the intervention group had a shorter duration of digestive symptoms compared with the control group: 2.6 ± 1.3 vs. 4.3 ± 2.2 days (p = 0.001); patients with non-severe disease on chest X-ray had shorter hospital stays: 8.1 ± 3.9 vs. 11.6 ± 7.4 days (p = 0.007). Conclusions: In this trial, the administration of a food supplement (Gasteel Plus®) was shown to be a protective factor in the group of patients with severe COVID-19 and allowed early recovery from digestive symptoms and a shorter hospital stay in patients with a normal–mild–moderate chest X-ray at admission (ClinicalTrials.gov number, NCT04666116).

Susceptibility to COVID-19 Nutrition Misinformation and Eating Behavior Change during Lockdowns: An International Web-Based Survey

To understand the susceptibility to nutrition-health misinformation related to preventing, treating, or mitigating the risk of COVID-19 during the initial lockdowns around the world, the present international web-based survey study (15 April-15 May 2020) gauged participants' (n = 3707) level of nutrition-health misinformation discernment by presenting them with 25 statements (including unfounded or unproven claims circulated at the time), alongside the influence of information sources of varying quality on the frequency of changes in their eating behavior and the extent of misinformation held, depending on the source used for such changes. Results revealed widespread misinformation about food, eating, and health practices related to COVID-19, with the 25 statements put to participants receiving up to 43% misinformed answers (e.g., 'It is safe to eat fruits and vegetables that have been washed with soap or diluted bleach'). Whereas higher quality information sources (nutrition scientists, nutrition professionals) had the biggest influence on eating behavior change, we found greater misinformation susceptibility when relying on poor quality sources for changing diet. Appropriate discernment of misinformation was weakest amongst participants who more frequently changed their eating behavior because of information from poor quality sources, suggesting disparities in the health risks/safety of the changes performed.

Modifiable contributing factors to COVID-19: A comprehensive review

The devastating complications of coronavirus disease 2019 (COVID-19) result from an individual's dysfunctional immune response following the initial severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Multiple toxic stressors and behaviors contribute to underlying immune system dysfunction. SARS-CoV-2 exploits the dysfunctional immune system to trigger a chain of events ultimately leading to COVID-19. The current study identifies eighty immune system dysfunction-enabling toxic stressors and behaviors (hereafter called modifiable contributing factors (CFs)) that also link directly to COVID-19. Each CF is assigned to one of the five categories in the CF taxonomy shown in Section 3.3.: Lifestyle (e.g., diet, substance abuse); Iatrogenic (e.g., drugs, surgery); Biotoxins (e.g., micro-organisms, mycotoxins); Occupational/Environmental (e.g., heavy metals, pesticides); Psychosocial/Socioeconomic (e.g., chronic stress, lower education). The current study shows how each modifiable factor contributes to decreased immune system capability, increased inflammation and coagulation, and increased neural damage and neurodegeneration. It is unclear how real progress can be made in combatting COVID-19 and other similar diseases caused by viral variants without addressing and eliminating these modifiable CFs.

Vitamin C as a Potential Interplaying Factor between Obesity and COVID-19 Outcome

(1) Background: Obesity is a risk factor for severe COVID-19 outcomes. Obesity can interfere with the action of vitamin C. The study aimed to investigate the association between BMI and severe outcomes of COVID-19 while considering vitamin C levels; (2) Methods: This was a retrospective study of 63 COVID-19 patients treated at the NMC Royal Hospital, United Arab Emirates; (3) Results: There was no significant difference in vitamin C levels among patients in all BMI categories (p > 0.05). The risk of severe COVID-19 significantly increased by 5.4 times among class 1 obese patients compared with normal BMI (OR = 5.40, 95%CI: (1.54−21.05), p = 0.010). Vitamin C did not affect the risk of COVID-19 severity or mortality across BMI categories (p = 0.177, p > 0.05, respectively). The time till viral clearance was significantly different among patients in different BMI categories when vitamin C levels were considered (p = 0.02). Although there was no significant difference in vitamin C levels across BMI categories, there was a significant interaction between vitamin C levels and viral clearance rate in obese patients; (4) Conclusions: Given the safety of vitamin C supplements and our findings, proper vitamin C uptake and supplementation for patients of various BMI levels are encouraged.

A Randomized, Double-Blind, Placebo-Controlled Investigation of Selenium Supplementation in Women at Elevated Risk for Breast Cancer: Lessons for Re-Emergent Interest in Selenium and Cancer

Damage to cellular macromolecules such as DNA and lipid, induced via reactive oxygen species, and indicators of cell proliferation potential such as insulin-like growth factor (IGF) metabolic status are intermediate biomarkers of breast cancer risk. Based on reports that selenium status can affect these markers, a randomized, placebo-controlled, double-blind experiment was conducted to investigate the potential of selenium supplementation to modulate breast cancer risk. Using a placebo tablet or a tablet containing 200 μg selenium provided as high-selenium yeast daily for one year, concentrations of the biomarkers in blood or urine were assessed at baseline and after 6 and 12 months of intervention. The selenium intervention used in this study is presumed to mediate its effect via the induction of glutathione peroxidase activity and the consequential impact of the active form of this protein on oxidative damage. We found no evidence to support this hypothesis or to indicate that systemic IGF metabolic status was affected. Critical knowledge gaps must be addressed for the resurgence of interest in selenium and cancer to garner clinical relevance. Those knowledge gaps include the identification of a specific, high-affinity selenium metabolite and the cellular target(s) to which it binds, and the demonstration that the cellular determinant that the selenium metabolite binds plays a critical role in the initiation, promotion, or progression of a specific type of cancer.

Consensus and Controversial Aspects of Vitamin D and COVID-19

OBJECTIVES

This work aims to review and discuss controversial topics in the field of vitamin D, SARS-CoV-2 infection, and COVID-19.

PARTICIPANTS

The International Conferences "Controversies in Vitamin D" are a series of workshops that started in 2017 featuring international experts and leaders in vitamin D research and clinical practice. The 5th annual conference was held in Stresa, Italy, from 15 to 18 September 2021.

EVIDENCE

Before the event, participants reviewed available studies on their assigned topic, drafted a related abstract, and presented their findings at the time of the conference. Relevant literature that became available since was also discussed within the panel and updated accordingly.

CONSENSUS

Before the event, the drafted abstracts had been merged to prepare a preliminary document. After the conference presentations, in-depth discussions in open sessions led to consensus. The document was subsequently modified according to discussions and up-to-date literature inclusion.

CONCLUSIONS

There is quite consistent evidence for an association between low 25 OH vitamin D (25(OH)D) levels and poor COVID-19 outcomes, despite heterogeneous publications of variable quality. However, the low vitamin D status in COVID-19 patients might also reflect reverse causality. Vitamin D supplementation might have a positive role in COVID-19 prevention. The evidence supporting a beneficial effect of vitamin D treatment in decreasing the risk of COVID-19 complications is conflicting. Conclusive statement regarding the beneficial effect of vitamin D in this context await high-quality randomized controlled trials.

Antioxidant, Anti-inflammatory, and Immunomodulatory Roles of Nonvitamin Antioxidants in Anti-SARS-CoV-2 Therapy

Viral pathologies encompass activation of pro-oxidative pathways and inflammatory burst. Alleviating overproduction of reactive oxygen species and cytokine storm in COVID-19 is essential to counteract the immunogenic damage in endothelium and alveolar membranes. Antioxidants alleviate oxidative stress, cytokine storm, hyperinflammation, and diminish the risk of organ failure. Direct antiviral roles imply: impact on viral spike protein, interference with the ACE2 receptor, inhibition of dipeptidyl peptidase 4, transmembrane protease serine 2 or furin, and impact on of helicase, papain-like protease, 3-chyomotrypsin like protease, and RNA-dependent RNA polymerase. Prooxidative environment favors conformational changes in the receptor binding domain, promoting the affinity of the spike protein for the host receptor. Viral pathologies imply a vicious cycle, oxidative stress promoting inflammatory responses, and vice versa. The same was noticed with respect to the relationship antioxidant impairment-viral replication. Timing, dosage, pro-oxidative activities, mutual influences, and interference with other antioxidants should be carefully regarded. Deficiency is linked to illness severity.

Vitamin C Supplementation for the Treatment of COVID-19: A Systematic Review and Meta-Analysis

Since the outbreak of the coronavirus disease 2019 (COVID-19) pandemic, caused by the severe respiratory syndrome coronavirus 2 (SARS-CoV-2), millions of people have died, and the medical system has faced significant difficulties. Our purpose was to perform a meta-analysis to estimate the effect of vitamin C on in-hospital mortality and the ICU or hospital length of stay for patients diagnosed with COVID-19. We conducted a systematic review with meta-analysis in the following databases: PubMed, Web of Science, Scopus and Cochrane Central Register of Controlled Trials. We included studies that evaluated the effect of vitamin C supplementation, compared with standard treatment in COVID-19 patients who are ≥18 y of age. Nineteen trials were included in the meta-analysis. In-hospital mortality with and without vitamin C supplementation was 24.1% vs. 33.9% (OR = 0.59; 95%CI: 0.37 to 0.95; p = 0.03), respectively. Sub-analysis showed that, in randomized clinical trials, in-hospital mortality varied and amounted to 23.9% vs. 35.8% (OR = 0.44; 95%CI: 0.25 to 0.76; p = 0.003), respectively. In the non-randomized trials, in-hospital mortality was 24.2% vs. 33.5% (OR = 0.72; 95%CI: 0.38 to 1.39; p = 0.33), respectively. The ICU length of stay was longer in patients treated with vitamin C vs. standard therapy, 11.1 (7.3) vs. 8.3 (4.7) days (MD = 1.91; 95%CI: 0.89 to 2.93; p < 0.001), respectively. Acute kidney injury in patients treated with and without vitamin C varied and amounted to 27.8% vs. 45.0% (OR = 0.56; 95%CI: 0.40 to 0.78; p < 0.001), respectively. There were no differences in the frequency of other adverse events among patients’ treatment with and without vitamin C (all p > 0.05). The use of vitamin C reduces hospital mortality. The length of stay in the ICU is longer among patients treated with vitamin C. In terms of patient safety, vitamin C has an acceptable profile. Low doses of vitamin C are effective and safe. Despite some evidence of the usefulness of vitamin C in modifying the course of COVID-19, it is too early to modify guidelines and recommendations. Further studies, in particular randomized clinical trials, are necessary.

Exploring nanoselenium to tackle mutated SARS-CoV-2 for efficient COVID-19 management

Despite ongoing public health measures and increasing vaccination rates, deaths and disease severity caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its new emergent variants continue to threaten the health of people around the world. Therefore, there is an urgent need to develop novel strategies for research, diagnosis, treatment, and government policies to combat the variant strains of SARS-CoV-2. Since the state-of-the-art COVID-19 pandemic, the role of selenium in dealing with COVID-19 disease has been widely discussed due to its importance as an essential micronutrient. This review aims at providing all antiviral activities of nanoselenium (Nano-Se) ever explored using different methods in the literature. We systematically summarize the studied antiviral activities of Nano-Se required to project it as an efficient antiviral system as a function of shape, size, and synthesis method. The outcomes of this article not only introduce Nano-Se to the scientific community but also motivate scholars to adopt Nano-Se to tackle any serious virus such as mutated SARS-CoV-2 to achieve an effective antiviral activity in a desired manner.

Effect of Omega-3 fatty acids supplementation on serum level of C-reactive protein in patients with COVID-19: a systematic review and meta-analysis of randomized controlled trials

Background

Omega-3 may alleviate the severity of coronavirus disease 2019 (COVID-19) by reducing the C-reactive protein (CRP) level, a marker for systemic inflammation. Because the scientific evidence indicating such a role is inconsistent, we aimed to evaluate the effect of Omega-3 on CRP change and CRP level in patients with COVID-19.

Methods

We conducted a comprehensive search on four databases (PubMed, Web of Science, EMBASE, and Scopus). We included all RCTs comparing Omega-3 with a control group regarding their effect on the CRP levels in patients with COVID-19. We used version two of the Cochrane risk of bias assessment tool to appraise the included studies. We extracted data to an online data extraction sheet. The primary outcomes were CRP change from baseline and CRP serum levels.

Results

We included four randomized controlled trials (RCTs) with 274 patients in this study. The overall effect estimate favored Omega-3 over the control group in terms of CRP change from baseline (mean difference (MD) =− 2.53, 95% confidence interval (CI): − 4.40, − 0.66) and CRP serum levels at the end of the study (MD =− 6.24, 95% CI: − 11.93, − 0.54).

Conclusion

Omega-3 showed promising effects on systemic inflammation by reducing CRP levels in COVID-19 patients. Based on this finding, we recommend Omega-3 for COVID-19 patients for its anti-inflammatory actions.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-022-03604-3.

The Prevalence of Dietary Supplement Use for the Purpose of COVID-19 Prevention in Japan

COVID-19 is still the biggest issue worldwide. Many dietary supplements on the market claim to have anti-COVID-19 effects without scientific evidence. To elucidate the prevalence of dietary supplement usage for the prevention of COVID-19, we conducted an online cross-sectional questionnaire survey among Japanese adults in January 2022. The prevalence of dietary supplement use for the prevention of COVID-19 was 8.3%, and there was no gender difference. We also conducted additional research on these dietary supplement users (1000 males and 1000 females). The most popular ingredient used was vitamin C (61.0%), with vitamin D (34.9%) and probiotics (33.4%) following. Half of these participants reported using supplements for more than one year. The information sources that reportedly led them to start using dietary supplements for the prevention of COVID-19 were the Internet (44.0%), television and radio (29.9%), and family or friends (26.0%), and these information sources differed among generations. In conclusion, some of the population used vitamin/mineral supplements for the prevention of COVID-19 that might be beneficial for their health, but some used ingredients with no scientifically proven effects against the virus at this time. Therefore, information-based scientific evidence is important to prevent the inappropriate use of dietary supplements by consumers.

Vitamin D prescribing practices among clinical practitioners during the COVID‐19 pandemic

Background and Aims

COVID‐19 has caused devastation globally. Low vitamin D status, particularly during the winter months, remains commonplace around the world, and it is thought to be one of the contributing factors toward causation and severity of COVID‐19. Many guidelines do not recommend vitamin D for the treatment or prevention of the disease. Hence, we set out to conduct a global survey to understand the use and prescribing habits of vitamin D among clinicians for COVID‐19.

Methods

An online anonymous questionnaire was sent to clinicians enquiring about their prescribing habits of vitamin D and personal use of vitamin D. Data of the survey were collected between January 15, 2021, and February 13, 2021.

Results

Four thousand four hundred forty practicing clinicians were included in the analysis, with the majority of those responding from Asia, followed by Europe. 82.9% prescribed vitamin D before COVID‐19, more commonly among general practitioners (GPs) in comparison with medical specialists, and Asian clinicians were more likely to prescribe vitamin D in comparison with Caucasian physicians (p < 0.01). GPs were also more likely to prescribe vitamin D prophylactically to prevent COVID‐19 in comparison with medical specialists (OR 1.47, p < 0.01). Most GPs (72.8%) would also prescribe vitamin D to treat COVID‐19 in comparison with medical specialists (OR 1.81, p < 0.01), as well as more Asian in comparison with Caucasian physicians (OR 4.57, p < 0.01). 80.4% of respondents were taking vitamin D, more so in the 45–54 and 65–74 age groups in comparison with the 18–24 years category (OR 2.15 and 2.40, respectively, both p < 0.05), many of whom did so before COVID‐19 (72.1%).

Conclusion

This survey has shown that many clinicians would prescribe vitamin D for the prevention and treatment of COVID‐19. The majority would also recommend measuring vitamin D levels, but not so in patients with COVID‐19.

The Perception of Minerals and Their Prevalence in Fortified Foods and Supplements in Japan

People’s intake of some minerals does not meet the nutrient reference values even in high-income countries. Recently, the deficiency of zinc and/or selenium has been considered to cause greater risk of COVID-19 infection and severity. To investigate consumer awareness, we conducted a cross-sectional questionnaire online survey among Japanese people (7500 males and 7500 females) concerning their perceptions of each mineral and the prevalence of mineral-fortified foods and/or mineral supplements. People’s perception of each mineral varied: the highest was for calcium (91.8%) and the lowest was for selenium (44.7%). In addition, only a portion of participants believed that they consumed a sufficient amount of each mineral; the highest was sodium (23.7%), and the lowest was manganese (5.2%). In addition, 18.2% of them felt that they could not consume enough sodium, even though most of the Japanese’s intake is excessive. Among mineral-fortified-food and/or mineral-supplement users, the purposes for these products were to maintain health (80.6%), supplement nutrients (48.0%), and prevent infectious diseases (23.2%). Only 18.4% of participants knew what amount they took. In conclusion, education is needed to prevent not only the insufficiency/deficiency of each mineral but also an excess intake of sodium.

Use of Incinerated Eggshells to Produce Pidan

Preserved eggs (pidans) are used in traditional Chinese cuisines. However, the alkaline conditions and metal ions generated during its preparation have caused some concerns. This study developed an innovative process for pidan processing using incinerated eggshell powder, an abundant by-product that can generate a highly alkaline solution and provide calcium ions (Ca2+). Either 0.5, 3, or 5% of the eggshell powder solution was used for basic pickling. Different combinations of ZnSO4 (0.175%), MgCl2 (0.08%), and CuSO4 (0.16%) were added. Duck eggs were pickled for 25 days at 25–27 °C, followed by 14 days of ripening. The pidan processed in 5% eggshell powder containing 0.175% ZnSO4 demonstrated the closest physiochemical and sensory characteristics to commercial pidans. Thus, the results offer a new technique to manufacture pidans and reduce the harmful impact of metal ions on human health and the environment.

The impact of immune dysfunction on perioperative complications in surgical COVID-19 patients: an imperative for early immunonutrition

Surgical patients with coronavirus disease 2019 (COVID-19) are vulnerable to increased perioperative complications and postoperative mortality, independent of the risk for contracting COVID-19 pneumonia after endotracheal intubation for general anesthesia. The presumed root cause of postoperative infections, microvascular soft tissue injuries and thromboembolic complications is largely attributed to the profound immune dysfunction induced by COVID-19 as a result of complement activation and the "cytokine storm". The empirical therapy with anti-inflammatory agents has been shown to attenuate some of the adverse effects of systemic hyperinflammation in COVID-19 patients. In addition, the proactive concept of "immunonutrition" may represent a new promising avenue for mitigating the complex immune dysregulation in COVID-19 and thereby reduce the rates of surgical complications and postoperative mortality. This letter provides a narrative summary of the current state-of-the-art in the field of immunonutrition as it pertains to surgical patient safety in COVID-19 patients.