Evaluation of vitamin D3 intakes up to 15,000 international units/day and serum 25-hydroxyvitamin D concentrations up to 300 nmol/L on calcium metabolism in a community setting

Healthcare Costs and Healthcare Utilization Outcomes of Vitamin D3 Supplementation at 5000 IU Daily during a 10.9 Month Observation Period within a Pragmatic Randomized Clinical Trial

Vitamin D insufficiency has been linked to multiple conditions including bone disease, respiratory disease, cardiovascular disease, diabetes, and cancer. Observational studies indicate lower healthcare costs and healthcare utilization with sufficient vitamin D levels. The secondary aims of our previously published pragmatic clinical trial of vitamin D3 supplementation were comparisons of healthcare costs and healthcare utilization. Comparisons were made between the vitamin D3 at 5000 IU supplementation group and a non-supplemented control group. Costs of care between the groups differed but were not statistically significant. Vitamin D3 supplementation reduced healthcare utilization in four major categories: hospitalizations for any reason (rate difference: -0.19 per 1000 person-days, 95%-CI: -0.21 to -0.17 per 1000 person-days, p < 0.0001); ICU admissions for any reason (rate difference: -0.06 per 1000 person-days, 95%-CI: -0.08 to -0.04 per 1000 person-days, p < 0.0001); emergency room visits for any reason (rate difference: -0.26 per 1000 person-days, 95%-CI: -0.46 to -0.05 per 1000 person-days, p = 0.0131; and hospitalizations due to COVID-19 (rate difference: -8.47 × 10-3 per 1000 person-days, 95%-CI: -0.02 to -1.05 × 10-3 per 1000 person-days, p = 0.0253). Appropriately powered studies of longer duration are recommended for replication of these utilization findings and analysis of cost differences.

Immunomodulatory Effects of Vitamin D in Respiratory Tract Infections and COVID-19 in Children

Acute respiratory tract infections (ARTIs) are one of the main reasons that the pediatric population goes to the doctor. The connection between ARTI and vitamin D (VD) is currently debated by the medical community, and so far, there has been little agreement with regard to the ideal level of 25(OH)D concentration that would provide protection for the respiratory tract, or the effectiveness of its administration in the treatment of respiratory infections. The purpose of this literature review was to bring attention to the immunomodulatory and antiviral function of vitamin D and its relation to the respiratory system by examining the main ARTIs, including SARS-CoV-2. The latter has affected the pediatric population in different ways, from asymptomatic patients to severe forms with multisystem inflammatory syndrome in children (MIS-C). Although there are not much clinical data on the SARS-CoV-2 disease in the pediatric population worldwide, we tried to find out whether there is a connection between the severity of this disease, other ARTIs, and vitamin D supplementation. We also aimed to find out if 25OHD deficiency had an adverse effect on the evolution of the disease and the recovery period in the case of younger patients affected by COVID-19. For this literature review, the PICO framework was selected as the methodological approach. Our results demonstrated many methods by which this vitamin may lower the risk of ARTI with regard to the COVID-19 infection. Despite these significant advancements, more research is needed to support the idea that 25(OH)D concentration can influence the evolution of respiratory tract infections in children.

Remote and semi-automated methods to conduct a decentralized randomized clinical trial

Introduction

Designing and conducting clinical trials is challenging for some institutions and researchers due to associated time and personnel requirements. We conducted recruitment, screening, informed consent, study product distribution, and data collection remotely. Our objective is to describe how to conduct a randomized clinical trial using remote and automated methods.

Methods

A randomized clinical trial in healthcare workers is used as a model. A random group of workers were invited to participate in the study through email. Following an automated process, interested individuals scheduled consent/screening interviews. Enrollees received study product by mail and surveys via email. Adherence to study product and safety were monitored with survey data review and via real-time safety alerts to study staff.

Results

A staff of 10 remotely screened 406 subjects and enrolled 299 over a 3-month period. Adherence to study product was 87%, and survey data completeness was 98.5% over 9 months. Participants and study staff scored the System Usability Scale 93.8% and 90%, respectively. The automated and remote methods allowed the study maintenance period to be managed by a small study team of two members, while safety monitoring was conducted by three to four team members. Conception of the trial to study completion was 21 months.

Conclusions

The remote and automated methods produced efficient subject recruitment with excellent study product adherence and data completeness. These methods can improve efficiency without sacrificing safety or quality. We share our XML file for researchers to use as a template for learning purposes or designing their own clinical trials.

Vitamin D3 Supplementation at 5000 IU Daily for the Prevention of Influenza-like Illness in Healthcare Workers: A Pragmatic Randomized Clinical Trial

Vitamin D supplementation has been shown to reduce the incidence of acute respiratory infections in populations at risk. The COVID-19 pandemic has highlighted the importance of preventing viral infections in healthcare workers. The aim of this study was to assess the hypothesis that vitamin D3 supplementation at 5000 IU daily reduces influenza-like illness (ILI), including COVID-19, in healthcare workers. We conducted a prospective, controlled trial at a tertiary university hospital. A random group of healthcare workers was invited to receive 5000 IU daily vitamin D3 supplementation for nine months, while other random healthcare system workers served as controls. All healthcare workers were required to self-monitor and report to employee health for COVID-19 testing when experiencing symptoms of ILI. COVID-19 test results were retrieved. Incidence rates were compared between the vitamin D and control groups. Workers in the intervention group were included in the analysis if they completed at least 2 months of supplementation to ensure adequate vitamin D levels. The primary analysis compared the incidence rate of all ILI, while secondary analyses examined incidence rates of COVID-19 ILI and non-COVID-19 ILI. Between October 2020 and November 2021, 255 healthcare workers (age 47 ± 12 years, 199 women) completed at least two months of vitamin D3 supplementation. The control group consisted of 2827 workers. Vitamin D3 5000 IU supplementation was associated with a lower risk of ILI (incidence rate difference: -1.7 × 10^-4/person-day, 95%-CI: -3.0 × 10^-4 to -3.3 × 10^-5/person-day, p = 0.015) and a lower incidence rate for non-COVID-19 ILI (incidence rate difference: -1.3 × 10^-4/person-day, 95%-CI -2.5 × 10^-4 to -7.1 × 10^-6/person-day, p = 0.038). COVID-19 ILI incidence was not statistically different (incidence rate difference: -4.2 × 10^-5/person-day, 95%-CI: -10.0 × 10^-5 to 1.5 × 10^-5/person-day, p = 0.152). Daily supplementation with 5000 IU vitamin D3 reduces influenza-like illness in healthcare workers.

Metabolomic analysis reveals the influence of IC50 vitamin D3 on RAW264.7 cells based on 1 H NMR and UPLC-MS/MS

BACKGROUND

As a lipid-soluble vitamin necessary for normal human physiology, vitamin D is mostly used in fortified foods, medicines and adjuvant treatment of diseases. However, taken in high doses, vitamin D can be toxic.

METHODS

We treated RAW264.7 cells with a semi-inhibitory concentration (IC₅₀ ) of vitamin D₃ . The metabolic changes in the treated cells were analyzed by ¹ H nuclear magnetic resonance (NMR) and ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS).

RESULTS

After treatment of RAW264.7 cells with an IC₅₀ dose of 55 μm vitamin D₃ , tunor necrosis factor-α levels decreased significantly and remarkable metabolic differences were also observed, with 12 types of metabolites were identified by ¹ H NMR and 87 identified by UPLC-MS/MS. Moreover, the metabolism of amino acids, sugars, lipids and other metabolic pathways were also affected.

CONCLUSION

Although vitamin D₃ is an indispensable nutrient in the body, excessive exposure has negative effects on cells and their metabolism. The present study will assist further analyses of the mechanism underlying vitamin D₃ toxicity. © 2022 Society of Chemical Industry.

Rapidly Increasing Serum 25(OH)D Boosts the Immune System, against Infections-Sepsis and COVID-19

Vitamin D deficiency is a global public health problem, a pandemic that commonly affects the elderly and those with comorbidities such as obesity, diabetes, hypertension, respiratory disorders, recurrent infections, immune deficiency, and malignancies, as well as ethnic minorities living in temperate countries. The same groups were worst affected by COVID-19. Since vitamin D deficiency weakens the immune system, it increases the risk of infections, complications, and deaths, such as from sepsis and COVID-19. Deficiency can be remedied cost-effectively through targeted food fortification, supplementation, and/or daily safe sun exposure. Its endocrine functions are limited to mineral metabolism, musculoskeletal systems, specific cell membrane interactions, and parathyroid gland functions. Except for the rapid, endocrine, and cell membrane-based non-genomic functions, all other biological and physiological activities of vitamin D depend on the adequate intracellular synthesis of 1,25(OH)2D (calcitriol) in peripheral target cells via the genome. Calcitriol mediates autocrine (intracrine) and paracrine signalling in immune cells, which provides broader, protective immune functions crucial to overcoming infections. The synthesis of 1,25(OH)2D (calcitriol) in peripheral target cells is dependent on diffusion and endocytosis of D3 and 25(OH)D from the circulation into them, which requires maintenance of serum 25(OH)D concentration above 50 ng/mL. Therefore, in acute infections such as sepsis and respiratory infections like COVID-19, it is necessary to rapidly provide its precursors, D3 and 25(OH)D, through the circulation to generate adequate intracellular calcitriol. Immune defence is one of the crucial non-hormonal functions of vitamin D. A single oral (bolus) dose or divided upfront loading doses between 100,000 and 500,000 IU, using 50,000 IU vitamin D3 increase the serum 25(OH)D concentrations to a therapeutic level of above 50 ng/mL that lasts between two to three months. This takes three to five days to raise serum 25(OH)D. In contrast, a single oral dose of calcifediol (0.014 mg/kg body weight) can generate the needed 25(OH)D concentration within four hours. Considering both D3 and 25(OH)D enter immune cells for generating calcitriol, using the combination of D3 (medium-term) and calcifediol (immediate) is cost-effective and leads to the best clinical outcome. To maximise protection against infections, particularly to reduce COVID-19-associated complications and deaths, healthcare workers should advise patients on safe sun exposure, adequate vitamin D supplementation and balanced diets containing zinc, magnesium, and other micronutrients to support the immune system. Meanwhile, governments, the World Health Organisation, the Centers for Disease Control, and governments should consider similar recommendations to physicians and the public, change the outdated vitamin D and other micronutrient recommendations directed to their population, and organise targetted food fortification programs for the vulnerable groups. This article discusses a rational approach to maintaining a sustained serum 25(OH)D concentration above 50 ng/mL, necessary to attain a robust immune system for overcoming infections. Such would cost-effectively improve the population’s health and reduce healthcare costs. It also describes three cost-effective, straightforward protocols for achieving and sustaining therapeutic serum 25(OH)D concentrations above 50 ng/mL (>125 nmol/L) to keep the population healthy, reduce absenteeism, improve productivity, and lower healthcare costs.

Absence of causal association between Vitamin D and bone mineral density across the lifespan: a Mendelian randomization study

Vitamin D deficiency is a candidate risk factor for osteoporosis, characterized by decreased bone mineral density (BMD). We performed this two-sample Mendelian randomization (MR) analysis to investigate the causal effect of vitamin D on BMD. We extracted 143 single-nucleotide polymorphisms from a recent GWAS on 417,580 participants of European ancestry as instrumental variables, and used summary statistics for BMD at forearm (n = 10,805), femoral neck (n = 49,988), lumbar spine (n = 44,731) and total-body of different age-stages (< 15, 15-30, 30-45, 45-60, > 60) (n = 67,358). We explored the direct effect of vitamin D on BMD with an adjusted body mass index (BMI) in a multivariable MR analysis. We found no support for causality of 25-hydroxyvitamin D on BMD at forearm, femoral neck, lumbar spine, and total-body BMD across the lifespan. There was no obvious difference between the total and direct effect of vitamin D on BMD after adjusting for BMI. Our MR analysis provided evidence that genetically determined vitamin D was not causally associated with BMD in the general population. Large-scale randomized controlled trials are warranted to investigate the role of vitamin D supplementation in preventing osteoporosis in the high-risk population.

A Narrative Review of the Evidence for Variations in Serum 25-Hydroxyvitamin D Concentration Thresholds for Optimal Health

Vitamin D3 has many important health benefits. Unfortunately, these benefits are not widely known among health care personnel and the general public. As a result, most of the world’s population has serum 25-hydroxyvitamin D (25(OH)D) concentrations far below optimal values. This narrative review examines the evidence for the major causes of death including cardiovascular disease, hypertension, cancer, type 2 diabetes mellitus, and COVID-19 with regard to sub-optimal 25(OH)D concentrations. Evidence for the beneficial effects comes from a variety of approaches including ecological and observational studies, studies of mechanisms, and Mendelian randomization studies. Although randomized controlled trials (RCTs) are generally considered the strongest form of evidence for pharmaceutical drugs, the study designs and the conduct of RCTs performed for vitamin D have mostly been flawed for the following reasons: they have been based on vitamin D dose rather than on baseline and achieved 25(OH)D concentrations; they have involved participants with 25(OH)D concentrations above the population mean; they have given low vitamin D doses; and they have permitted other sources of vitamin D. Thus, the strongest evidence generally comes from the other types of studies. The general finding is that optimal 25(OH)D concentrations to support health and wellbeing are above 30 ng/mL (75 nmol/L) for cardiovascular disease and all-cause mortality rate, whereas the thresholds for several other outcomes appear to range up to 40 or 50 ng/mL. The most efficient way to achieve these concentrations is through vitamin D supplementation. Although additional studies are warranted, raising serum 25(OH)D concentrations to optimal concentrations will result in a significant reduction in preventable illness and death.

Can vitamin D be considered an adiponectin secretagogue? A systematic review and meta-analysis

There is some evidence for ameliorating effect of vitamin D on glycemic and lipidemic status which are likely to be mediated through other molecules including adiponectin. However, the overall results have been controversial. This study was conducted to evaluate the effect of vitamin D supplementation on serum adiponectin concentration. MEDLINE, PubMed, Embase, Cochrane Library, and Google Scholar were searched and 402 studies were found in a preliminary search. After screening of titles and abstracts nine studies were selected. Pooled data showed no significant effect on adiponectin concentrations (mean difference (MD) 0.37, 95 % CI: -0.1 to 0.87). However, there was a significant effect in a subgroup of participants who had diabetes (MD: 0.03, 95 % CI: 0.00 to 0.05, p = 0.029). The treatment effect on adiponectin concentrations was significant in those trials that used supplementation on a daily basis (MD: 0.03, 95 % CI: 0.00 to 0.05, p = 0.028) and vitamin D plus calcium (MD: 0.04, 95 % CI: 0.01 to 0.07, p = 0.014). The meta-regression revealed a significant association between BMI and age of participants at baseline and the treatment effect (B, -0.144, 95 % CI: -0.276 to -0.011, p = 0.033 and B, -0.043, 95 % CI: -0.075 to -0.012, p = 0.006). The results of this meta-analysis study indicates that vitamin D may be considered an adiponectin secretagogue in subjects with diabetes and this effect may be potentiated if vitamin D intake is on daily basis and in combination with calcium but can be weakened by increasing BMI.

Personalise vitamin D3 using physiologically based pharmacokinetic modelling

Plasma concentration of vitamin D₃ metabolite 25-hydroxyvitamin D₃ (25(OH)D₃ ) is variable among individuals. The objective of this study is to establish an accurate model for 25(OH)D₃ pharmacokinetics (PKs) to support selection of a suitable dose regimen for an individual. We collated vitamin D₃ and 25(OH)D₃ plasma PK data from reported clinical trials and developed a physiologically-based pharmacokinetic (PBPK) model to appropriately recapitulate training data. Model predictions were then qualified with 25(OH)D₃ plasma PKs under vitamin D₃ and 25(OH)D₃ dose regimens distinct from training data. From data exploration, we observed the increase in plasma 25(OH)D₃ after repeated dosing was negatively correlated with 25(OH)D₃ baseline levels. Our final model included a first-order vitamin D₃ absorption, a first-order vitamin D₃ metabolism, and a nonlinear 25(OH)D₃ elimination function. This structure explained the apparent paradox. Remarkably, the model accurately predicted plasma 25(OH)D₃ following repeated dosing up to 1250 μg/d in the test set. It also made sensible predictions for large single vitamin D₃ doses up to 50,000 μg in the test set. Model predicts 10 μg/d regimen may be ineffective for achieving sufficiency (plasma 25(OH)D₃ ≥ 75 nmol/L) for a severely deficient individual (baseline 25(OH)D₃ = 10 nmol/L), and it might take the same person over 200 days to reach sufficiency at 20 μg/d dose. We propose to personalize vitamin D₃ supplementation protocol with this PBPK model. It would require measuring 25(OH)D₃ baseline levels, which is not routinely performed under the current UK public health advice. STUDY HIGHLIGHTS: WHAT IS THE CURRENT KNOWLEDGE ON THE TOPIC? Vitamin D PK exhibits substantial inter-individual variability. Different officially recommended daily doses are confusing. ​ WHAT QUESTION DID THIS STUDY ADDRESS? Is the UK's recommended 10 µg daily dose sufficient? Should everyone be given same dose? ​ WHAT DOES THIS STUDY ADD TO OUR KNOWLEDGE? Our model accurately predicts plasma 25(OH)D under daily oral administration of vitamin D₃ . The 10 µg daily vitamin D₃ dose is insufficient for prophylaxis (plasma 25(OH)D at 75 nmol/L). ​ HOW MIGHT THIS CHANGE DRUG DISCOVERY, DEVELOPMENT, AND/OR THERAPEUTICS? Combining blood test to measure 25(OH)D baseline with this PBPK model will help inform dosage selection and select follow-up date to improve effectiveness of Hypovitaminosis D treatment.

Vitamin D3 supplementation does not enhance the effects of resistance training in older adults

BACKGROUND

Lifestyle therapy with resistance training is a potent measure to counteract age-related loss in muscle strength and mass. Unfortunately, many individuals fail to respond in the expected manner. This phenomenon is particularly common among older adults and those with chronic diseases (e.g. chronic obstructive pulmonary disease, COPD) and may involve endocrine variables such as vitamin D. At present, the effects of vitamin D supplementation on responses to resistance training remain largely unexplored.

METHODS

Ninety-five male and female participants (healthy, n = 71; COPD, n = 24; age 68 ± 5 years) were randomly assigned to receive either vitamin D3 or placebo supplementation for 28 weeks in a double-blinded manner (latitude 61°N, September-May). Seventy-eight participants completed the RCT, which was initiated by 12 weeks of supplementation-only (two weeks with 10 000 IU/day, followed by 2000 IU/day), followed by 13 weeks of combined supplementation (2000 IU/day) and supervised whole-body resistance training (twice weekly), interspersed with testing and measurements. Outcome measures included multiple assessments of muscle strength (nvariables  = 7), endurance performance (n = 6), and muscle mass (n = 3, legs, primary), as well as muscle quality (legs), muscle biology (m. vastus lateralis; muscle fibre characteristics, transcriptome), and health-related variables (e.g. visceral fat mass and blood lipid profile). For main outcome domains such as muscle strength and muscle mass, weighted combined factors were calculated from the range of singular assessments.

RESULTS

Overall, 13 weeks of resistance training increased muscle strength (13% ± 8%), muscle mass (9% ± 8%), and endurance performance (one-legged, 23% ± 15%; whole-body, 8% ± 7%), assessed as weighted combined factors, and were associated with changes in health variables (e.g. visceral fat, -6% ± 21%; [LDL]serum , -4% ± 14%) and muscle tissue characteristics such as fibre type proportions (e.g. IIX, -3% points), myonuclei per fibre (30% ± 65%), total RNA/rRNA abundances (15%/6-19%), and transcriptome profiles (e.g. 312 differentially expressed genes). Vitamin D3 supplementation did not affect training-associated changes for any of the main outcome domains, despite robust increases in [25(OH)D]serum (∆49% vs. placebo). No conditional effects were observed for COPD vs. healthy or pre-RCT [25(OH)D]serum . In secondary analyses, vitamin D3 affected expression of gene sets involved in vascular functions in muscle tissue and strength gains in participants with high fat mass, which advocates further study.

CONCLUSIONS

Vitamin D3 supplementation did not affect muscular responses to resistance training in older adults with or without COPD.

Fat-Soluble Vitamins and the Current Global Pandemic of COVID-19: Evidence-Based Efficacy from Literature Review

The outbreak of pneumonia caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), later named COVID-19 by the World Health Organization (WHO), was initiated at Wuhan, Hubei, China, and there was a rapid spread of novel SARS-CoV-2 and the disease COVID-19 in late 2019. The entire world is now experiencing the challenge of COVID-19 infection. However, still very few evidence-based treatment options are available for the prevention and treatment of COVID-19 disease. The present review aims to summarize the publicly available information to give a comprehensive yet balanced scientific overview of all the fat-soluble vitamins concerning their role in SARS-CoV-2 virus infection. The roles of different fat-soluble vitamins and micronutrients in combating SARS-CoV-2 infection have been recently explored in several studies. There are various hypotheses to suggest their use to minimize the severity of COVID-19 infection. These vitamins are pivotal in the maintenance and modulation of innate and cell-mediated, and antibody-mediated immune responses. The data reported in recent literature demonstrate that deficiency in one or more of these vitamins compromises the patients’ immune response and makes them more vulnerable to viral infections and perhaps worse disease prognosis. Vitamins A, D, E, and K boost the body’s defense mechanism against COVID-19 infection and specifically prevent its complications such as cytokine storm and other inflammatory processes, leading to increased morbidity and mortality overemphasis. However, more detailed randomized double-blind clinical pieces of evidence are required to define the use of these supplements in preventing or reducing the severity of the COVID-19 infection.

Oral and Topical Vitamin D, Sunshine, and UVB Phototherapy Safely Control Psoriasis in Patients with Normal Pretreatment Serum 25-Hydroxyvitamin D Concentrations: A Literature Review and Discussion of Health Implications

Vitamin D, sunshine and UVB phototherapy were first reported in the early 1900s to control psoriasis, cure rickets and cure tuberculosis (TB). Vitamin D also controlled asthma and rheumatoid arthritis with intakes ranging from 60,000 to 600,000 International Units (IU)/day. In the 1980s, interest in treating psoriasis with vitamin D rekindled. Since 1985 four different oral forms of vitamin D (D2, D3, 1-hydroxyvitaminD3 (1(OH)D3) and 1,25-dihydroxyvitaminD3 (calcitriol)) and several topical formulations have been reported safe and effective treatments for psoriasis-as has UVB phototherapy and sunshine. In this review we show that many pre-treatment serum 25(OH)D concentrations fall within the current range of normal, while many post-treatment concentrations fall outside the upper limit of this normal (100 ng/mL). Yet, psoriasis patients showed significant clinical improvement without complications using these treatments. Current estimates of vitamin D sufficiency appear to underestimate serum 25(OH)D concentrations required for optimal health in psoriasis patients, while concentrations associated with adverse events appear to be much higher than current estimates of safe serum 25(OH)D concentrations. Based on these observations, the therapeutic index for vitamin D needs to be reexamined in the treatment of psoriasis and other diseases strongly linked to vitamin D deficiency, including COVID-19 infections, which may also improve safely with sufficient vitamin D intake or UVB exposure.

Nutritional status of micronutrients as a possible and modifiable risk factor for COVID-19: a UK perspective

Recent scientific evidence has indicated that the elderly have increased risk of COVID-19 infections, with over 70s and 80s being hardest hit - especially residents of care homes and in clinical settings, ethnic minorities, people who work indoors and those who are overweight and obese. Other potential risk factors include lack of exposure to sunlight, darker skin pigmentation, co-morbidities, poor diet, certain medications, disadvantaged social and economic status, and lifestyle factors such as smoking and excessive consumption of alcohol. A key question is to understand how and why certain groups of people are more susceptible to COVID-19, whether they have weakened immune systems and what the roles of good nutrition and specific micronutrients are in supporting immune functions. A varied and balanced diet with an abundance of fruits and vegetables and the essential nutrients like vitamin D, vitamin A, B vitamins (folate, vitamin B6 and vitamin B12), vitamin C and the minerals, Fe, Cu, Se and Zn are all known to contribute to the normal functions of the immune system. Avoidance of deficiencies and identification of suboptimal intakes of these micronutrients in targeted groups of patients and in distinct and highly sensitive populations could help to strengthen the resilience of people to the COVID-19 pandemic. It is important to highlight evidence-based public health messages, to prevent false and misleading claims about the benefits of foods and food supplements and to communicate clearly that the extent of knowledge between micronutrients and COVID-19 infection is still being explored and that no diet will prevent or cure COVID-19 infection. Frequent handwashing and social distancing will be critical to reduce transmission.

Association Between Vitamin D and Novel SARS-CoV-2 Respiratory Dysfunction - A Scoping Review of Current Evidence and Its Implication for COVID-19 Pandemic

OBJECTIVES

To assess the association between vitamin D deficiency and increased morbidity/mortality with COVID-19 respiratory dysfunction.

DESIGN

Scoping review.

DATA SOURCES

Ovid MEDLINE (1946 to 24 of April 2020) and PubMed (2020 to 17 of September 2020).

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

A search using the search terms: [(cholecalciferol or ergocalciferol or vitamin D2 or vitamin D3 or vitamin D or 25OHD) and (SARS-CoV-2 or coronavirus or COVID or betacoronavirus or MERS-CoV or SARS-CoV or respiratory infection or acute respiratory distress syndrome or ARDS)]m.p. was conducted on the 24/04/2020 (Search A) and 17/09/2020 (Search B).

RESULTS

91 studies were identified as being concerned with Acute Respiratory Infection (ARI)/Acute Respiratory Distress Syndrome (ARDS) and vitamin D, and 25 publications specifically explored the role of vitamin D deficiency in the development and progression of SARS-CoV-2/COVID-19 related ARDS. Search "A" identified three main themes of indirect evidence supporting such an association. Consistent epidemiological evidence exists linking low vitamin D levels to increased risk and severity of respiratory tract infections. We also report on plausible biological processes supporting such an association; and present weaker evidence supporting the benefit of vitamin D supplementation in reducing the risk and severity of ARIs. Uncertainty remains about what constitutes an appropriate dosing regimen in relation to reducing risk/severity of ARI/ARDS. More recent evidence (Search B) provided new insights into some direct links between vitamin D and COVID-19; with a number of cohort and ecological studies supporting an association with PCR-positivity for SARS-CoV-2 and vitamin D deficiency. The exact efficacy of the vitamin D supplementation for prevention of, or as an adjunct treatment for COVID-19 remains to be determined; but a number of randomized control trials (RCTs) currently underway are actively investigating these potential benefits.

CONCLUSION

Our rapid review of literature supports the need for observational studies with COVID-19 infected populations to measure and assess vitamin D levels in relation to risk/severity and outcomes; alongside RCTs designed to evaluate the efficacy of supplementation both in preventive and therapeutic contexts. The overlap in the vitamin D associated biological pathways with the dysregulation reported to drive COVID-19 outcomes warrants further investigation.

A Basic Review of the Preliminary Evidence That COVID-19 Risk and Severity Is Increased in Vitamin D Deficiency

As the world's attention has been riveted upon the growing COVID-19 pandemic, many researchers have written brief reports supporting the hypothesis that vitamin D deficiency is related to the incidence and severity of COVID-19. The clear common thread among the top risk groups-vitamin D deficiency-may be being overlooked because of previous overstated claims of vitamin D benefits. However, the need to decrease COVID-19 fatalities among high-risk populations is urgent. Early researchers reported three striking patterns. Firstly, the innate immune system is impaired by vitamin D deficiency, which would predispose sufferers to viral infections such as COVID-19. Vitamin D deficiency also increases the activity of the X-chromosome-linked "Renin-Angiotensin" System, making vitamin D deficient individuals (especially men) more susceptible to COVID-19's deadly "cytokine storm" (dramatic immune system overreaction). Secondly, the groups who are at highest risk for severe COVID-19 match those who are at highest risk for severe vitamin D deficiency. This includes the elderly, men, ethnic groups whose skin is naturally rich in melanin (if living outside the tropics), those who avoid sun exposure for cultural and health reasons, those who live in institutions, the obese, and/or those who suffer with hypertension, cardiovascular disease, or diabetes. And thirdly, the pattern of geographical spread of COVID-19 reflects higher population vitamin D deficiency. Both within the USA and throughout the world, COVID-19 fatality rates parallel vitamin D deficiency rates. A literature search was performed on PubMed, Google Scholar, and RSMLDS, with targeted Google searches providing additional sources. Although randomized controlled trial results may be available eventually, the correlational and causal study evidence supporting a link between vitamin D deficiency and COVID-19 risks is already so strong that it supports action. The 141 author groups writing primarily about biological plausibility detailed how vitamin D deficiency can explain every risk factor and every complication of COVID-19, but agreed that other factors are undoubtedly at work. COVID-19 was compared with dengue fever, for which oral vitamin D supplements of 4,000 IU for 10 days were significantly more effective than 1,000 IU in reducing virus replication and controlling the "cytokine storm" (dramatic immune system over-reaction) responsible for fatalities. Among the 47 original research studies summarized here, chart reviews found that serum vitamin D levels predicted COVID-19 mortality rates (16 studies) and linearly predicted COVID-19 illness severity (8 studies). Two causal modeling studies and several analyses of variance strongly supported the hypothesis that vitamin D deficiency is a causal, rather than a bystander, factor in COVID-19 outcomes. Three of the four studies whose findings opposed the hypothesis relied upon disproven assumptions. The literature review also found that prophylactically correcting possible vitamin D deficiency during the COVID-19 pandemic is extremely safe. Widely recommending 2,000 IU of vitamin D daily for all populations with limited ability to manufacture vitamin D from the sun has virtually no potential for harm and is reasonably likely to save many lives.

Official recommendations for vitamin D through the life stages in developed countries

Inadequate vitamin D nutritional status is prevalent worldwide and has been associated with autoimmune disorders, heart disease, deadly cancers, insulin resistance, inflammation, neurological disorders, adverse outcomes in pregnancy, and increased risk for mortality. Expert recommendations for vitamin D intake differ between governmental agencies and practice guidelines from medical societies due to differences in the definition of vitamin D deficiency, insufficiency and sufficiency based on serum 25-hydroxyvitamin D [25(OH)D] concentrations. In addition, separate health promotion bodies also provide targeted recommendations for the prevention of specific disorders such as reducing risk for developing some cancers and autoimmune diseases. We review and provide perspectives regarding various recommendations from the Institute of Medicine (IOM, United States) and Health Canada, the European Food Safety Authority (EFSA), the Scientific Advisory Committee on Nutrition (SACN; United Kingdom), the World Health Organization, the Endocrine Society and other expert groups by life stage as a guide intended for clinician use.

Supplemental vitamin D3 does not affect musculoskeletal or psychomotor performance in college aged males

The experiment examined the effects 4 weeks of vitamin D (Vit D) supplementation versus placebo on musculoskeletal and psychomotor performance. Thirty-two college age males (Age: 22 ± 4 y, Height: 177.7 ± 8.3 cm, Weight: 81.5 ± 14.6 kg, BF%: 19.6 ± 7.9, Vit D: 20.0 ± 7.2 ng/ml). Participants were assigned to group (Vit D vs placebo) and remained blind throughout the study. The treatments were 4000 IU of Vit D3 or placebo (dextrose) administered daily for 4 weeks. The participants underwent baseline testing for isometric strength, explosive ability and psychomotor performance, which was repeated at week 2 and week 4. Isometric tests consisted of an Isometric Mid Thigh Pull on a Force Plate (IMTP) and an upper body isometric test (UBIST) using a load cell. Peak force during a countermovement jump (CMJ) was also determined via force plate. A psychomotor vigilance test (PVT) was used to measure sustained reaction time. Analysis of the UBIST data did not reveal a significant group × time interaction (p = 0.14; Vit D pre: 553.7 ± 168.3 N, post: 585.5 ± 150.2 N; Placebo pre: 677.7 ± 182.3 N, post: 649.8 ± 236.9 N). For IMTP no significant group × time interaction (p = 0.83; Vit D pre: 2596.4 ± 342.3 N, post: 2606.9 ± 378.3 N; Placebo pre: 2684.0 ± 432.9 N, post: 2762.6 ± 440.4 N) was found. CMJ analysis did not reveal interaction effects for group × time (p = 0.21; Vit D pre: 4429.7 ± 1619.0 N, post: 4938.5 ± 2374.8 N; Placebo pre: 5537.3 ± 3027.0 N, post: 6266.9 ± 4577.3 N). For PVT (mean reaction time) there was no significant interaction effects for group × time (p = 0.35; Vit D pre: 0.304 ± 0.041 sec, post: 0.301 ± 0.053 sec; Placebo pre: 0.295 ± 0.044 sec, post: 0.284 ± 0.029 sec). In conclusion, four weeks of Vit D supplementation was not effective in increasing musculoskeletal or psychomotor performance.

Retrospective Analysis of Cardiovascular Disease Risk Parameters in Participants of a Preventive Health and Wellness Program

Lifestyle, dietary, and nutritional choices are important influencing parameters of cardiovascular disease (CVD) risk, the number one cause of morbidity and mortality globally. Our aims were to i) characterize CVD risk parameters using data from 7939 participants enrolled in a preventive health and wellness program between March 2010 and January 2017; and ii) evaluate intervention effects in 3,020 participants who returned for follow-up. Blood measurements (nutrient markers), CVD risk parameters (abdominal obesity, hypertension, hyperglycemia, hypertriglyceridemia, low high-density lipoprotein (HDL), insulin resistance, and inflammation), glycemic status (HbA1c), and insulin resistance (HOMA-IR) were assessed. Framingham and Reynold's risk scores were also calculated. After approximately one year of treatment (n = 3 020), mean arachidonic acid:eicosapentaenoic acid (AA:EPA) ratio, homocysteine, and HbA_lc concentrations were significantly reduced; other risk parameters did not improve but mean values remained within reference ranges. Excluding participants taking related medications, 38.8%, 37.2%, 38.0%, 42.5%, and 59.7% of those with hyperglycemia, hypertriglyceridemia, low HDL, insulin resistance, or prediabetes, respectively, at baseline no longer had the condition at follow-up. In contrast, of individuals within the reference range at baseline, new cases at follow-up were found for 10.1%, 12.2%, 6.3%, 8.2%, and 7.6% (as above, respectively). Regression models revealed a significant association between serum 25-hydroxyvitamin D concentrations ≥100 nmol/L and reductions in many CVD risk parameters after adjustment for confounding variables. These findings suggest that a preventive approach to health and wellness focused on nutrients, optimal serum 25-hydroxyvitamin D concentrations, and lifestyle changes has the potential to reduce the risk of CVD.

Daily oral dosing of vitamin D3 using 5000 TO 50,000 international units a day in long-term hospitalized patients: Insights from a seven year experience

Vitamin D3 is a secosteroid hormone produced in the skin in amounts estimated up to 25,000 international units (IUs) a day by the action of UVB radiation on 7-dehydrocholesterol. Vitamin D deficiency is common due to both lack of adequate sun exposure to the skin, and because vitamin D is present in very few food sources. Deficiency is strongly linked to increased risk for a multitude of diseases, several of which have historically been shown to improve dramatically with either adequate UVB exposure to the skin, or to oral or topical supplementation with vitamin D. These diseases include asthma, psoriasis, rheumatoid arthritis, rickets and tuberculosis. All patients in our hospital have been routinely screened on admission for vitamin D deficiency since July 2011, and offered supplementation to either correct or prevent deficiency. During this time, we have admitted over 4700 patients, the vast majority of whom agreed to supplementation with either 5000 or 10,000 IUs/day. Due to disease concerns, a few agreed to larger amounts, ranging from 20,000 to 50,000 IUs/day. There have been no cases of vitamin D3 induced hypercalcemia or any adverse events attributable to vitamin D3 supplementation in any patient. Three patients with psoriasis showed marked clinical improvement in their skin using 20,000 to 50,000 IUs/day. Analysis of 777 recently tested patients (new and long-term) not on D3 revealed 28.7% with 25-hydroxyvitaminD3 (25OHD3) blood levels < 20 ng/ml, 64.1% < 30 ng/ml, a mean 25OHD3 level of 27.1 ng/ml, with a range from 4.9 to 74.8 ng/ml. Analysis of 418 inpatients on D3 long enough to develop 25OHD3 blood levels > 74.4 ng/ml showed a mean 25OHD3 level of 118.9 ng/ml, with a range from 74.4 to 384.8 ng/ml. The average serum calcium level in these 2 groups was 9.5 (no D3) vs 9.6 (D3), with ranges of 8.4 to 10.7 (no D3) vs 8.6 to 10.7 mg/dl (D3), after excluding patients with other causes of hypercalcemia. The average intact parathyroid hormone levels were 24.2 pg/ml (D3) vs. 30.2 pg/ml (no D3). In summary, long-term supplementation with vitamin D3 in doses ranging from 5000 to 50,000 IUs/day appears to be safe.

Concerns About The Integrity of The Scientific Research Process-Focus On Recent Negative Publications Regarding Nutrition, Multivitamins, Fish Oil And Cardiovascular Disease

The next step in reestablishing credibility seams to us honesty and recognizing we all share a common goal of the health and wellness of the human community and the planet. Everyone agrees that the current healthcare system, despite its many incredible successes, is also showing its limitations and is no longer sustainable. We believe the solution starts with us the researchers and editors. A good first step might be formally recognizing the errors and showing how we can and intend to get better.

Effect of 16-weeks vitamin D replacement on calcium-phosphate homeostasis in overweight and obese adults

This randomised placebo-controlled trial aimed to determine the effect of 16-weeks cholecalciferol supplementation on calcium-phosphate homeostasis and bone mineral density (BMD) in overweight and obese adults. Fifty-four vitamin D-deficient (25OHD<50 nmol/L), overweight and obese adults (mean age 32 ± 8.5 years) were included in the trial. Participants were randomly assigned to receive either a bolus oral dose of 100,000 IU cholecalciferol followed by 4000 IU cholecalciferol/d or a matching placebo for 16 weeks. Before and after the intervention, serum calcium, phosphate, 25-hydroxyvitamin D [25(OH)D], intact parathyroid hormone (iPTH) and C-terminal plasma fibroblast growth factor-23 (cFGF-23) concentrations were measured. Whole-body BMD was assessed using dual-energy X-ray absorptiometry (DXA) and diet and sun exposure were assessed using self-administered questionnaires. There were no significant differences in baseline characteristics between the vitamin D and placebo group. After 16-weeks of vitamin D supplementation, mean changes in 25(OH)D concentration were higher in the vitamin D group (57 nmol/L 95% CI 49, 65) compared with placebo (2 nmol/L 95% CI -4, 8), P < 0.001. Additionally, iPTH concentrations declined in the vitamin D group (-1.19 pmol/L 95% CI -1.9, -0.47) compared with placebo (0.14 pmol/L 95% CI -0.49, 0.77), P = 0.006. There were no significant differences in calcium, phosphate, iPTH and cFGF-23 concentrations and whole-body BMD between vitamin D and placebo at follow-up. Inverse correlations were observed between mean change in serum iPTH and cFGF-23 in the vitamin D group only (r=-0.41, P = 0.029). In individuals with greater vitamin D deficiency at baseline (25(OH)D < 30 nmol/L), there was a significant increase in mean whole-body BMD (0.01 g/cm², 95% CI 0.001, 0.025) however, the mean change in BMD was not different between vitamin D and placebo groups in this sub-group analysis. We conclude that cholecalciferol supplementation for 16 weeks increases serum 25(OH)D concentrations and reduces iPTH concentrations in overweight and obese, but otherwise healthy adults with vitamin D deficiency, and has no effect on calcium, phosphate and iFGF-23 concentrations and whole-body BMD.

Sex-specific correlation of IGFBP-2 and IGFBP-3 with vitamin D status in adults with obesity: a cross-sectional serum proteomics study

Objective

Subjects with low vitamin D levels are at risk of cardiometabolic disease. The aim of this study was to identify novel serological markers linking vitamin D status with cardiometabolic profile in non-diabetic adults with obesity.

Methods

For the discovery phase, we used quantitative serum proteomics in sex-matched, age-matched and BMI-matched subjects with obesity [BMI: 25–35 kg/m²] and low [25(OH)D < 50 nmol/L] vs. high vitamin D status [25(OH)D > 50 nmol/L] (n = 16). For the validation phase, we performed ELISA in a larger cohort with similar characteristics (n = 179).

Results

We identified 423 and 549 differentially expressed proteins in the high vs. low vitamin D groups of the male and female cohorts, respectively. The small molecule biochemistry protein networks and the glycolysis|gluconeogenesis pathway were significantly enriched in the DEPs of both sexes. As surrogate markers to these processes, the insulin-like growth factor binding protein -2  (IGFBP-2) was upregulated in males, whereas   IGFBP-3 was upregulated in females from the high Vitamin D status. This sex-specific trend  was confirmed using Luminex ELISA to an independent but clinically analogous cohort of males (n = 84, p = 0.002) and females (n = 95, p = 0.03).

Conclusions

The high Vitamin D status correlated with the serological upregulation of IGFBP-2 in males and IGFBP-3 in females with obesity and may constitute surrogate markers of risk reduction of cardiometabolic disease.

Association between Blood 25-Hydroxyvitamin D Levels and Survival in Colorectal Cancer Patients: An Updated Systematic Review and Meta-Analysis

Previous meta-analyses have shown an improved survival with higher blood 25-hydroxyvitamin D (25(OH)D) concentrations in patients with colorectal cancer (CRC). However, a number of much larger studies have been published since then. We provide an updated meta-analysis to synthesize current evidence. PubMed and Web of Science databases were systematically searched for eligible studies. The dose-response relationships and pooled hazard ratios for overall and CRC-specific survival comparing the highest versus the lowest categories of blood 25(OH)D concentrations were assessed. Subgroup analyses based on study geographic location, year of publication, sample size, length of follow-up time and stage were conducted to explore potential sources of heterogeneity. Overall, 11 original studies with a total of 7718 CRC patients were included. The dose-response meta-analysis showed an improvement in survival outcomes with increasing blood 25(OH)D concentrations. Pooled hazard ratios (95% confidence intervals) comparing highest versus lowest categories were 0.68 (0.55–0.85) and 0.67 (0.57–0.78) for overall and CRC-specific survival, respectively. Associations were more prominent among studies conducted in Europe, with larger sample sizes, and including stage I–IV patients. This updated meta-analysis reveals robust evidence of an association between higher blood 25(OH)D concentrations and better survival in CRC patients. The potential for enhancing prognosis of CRC patients by vitamin D supplementation should be explored by randomized trials.

Vitamin D Supplementation, Serum 25(OH)D Concentrations and Cardiovascular Disease Risk Factors: A Systematic Review and Meta-Analysis

Background: Cardiovascular disease (CVD) risk factors are associated with low serum 25 hydroxyvitamin D (25(OH)D) concentrations in observational studies; however, clinical trial findings are inconsistent.

Objective: We assessed the effect of vitamin D supplementation and increased serum 25(OH)D concentrations on CVD risk factors in a systemic review and meta-analysis of randomized controlled trials (RCTs).

Design: MEDLINE, CINAHL, EMBASE, and Google Scholar were searched for RCTs that evaluated vitamin D supplementation and cardiovascular outcomes [blood pressure, parathyroid hormone (PTH), serum high-sensitivity C-reactive protein (hs-CRP), total cholesterol, high and low density lipoprotein (HDL and LDL, respectively), triglycerides, peak wave velocity (PWV) and Augmentation Index (AI)] from 1992 through 2017. Meta-analysis was based on a random-effects model and inverse variance method to calculate standardized mean difference (SMD) as effect sizes, followed by a leave-one-out method for sensitivity analysis. Risk of publication bias was assessed using Cochrane checklist and Begg funnel plots. The systematic review is registered as CRD42015025346.

Results: We identified 2341 studies from which 81 met inclusion criteria. The meta-analysis indicated a significant reduction in systolic blood pressure (SMD = −0.102 ± 0.04 mmHg, 95% confidence interval (CI), −0.20 to −0.03), diastolic blood pressure (SMD = −0.07 ± 0.03 mmHg, 95% CI, −0.14 to −0.006), serum PTH (SMD = −0.66 ± 0.08 ng/L, 95% CI, −0.82 to −0.49), hs-CRP (SMD = −0.20 ± 0.07 mg/L, 95% CI, −0.34 to −0.06), total cholesterol (SMD = −0.15 ± 0.06 mmol/L, 95% CI, −0.25 to −0.04), LDL (SMD = −0.10 ± 0.05 mmol/L, 95% CI, −0.20 to −0.003), triglycerides (SMD = −0.12 ± 0.06 mmol/L, 95% CI, −0.23 to −0.003) and a significant increase in HDL (SMD = 0.09 ± 0.04 mmol/L, 95% CI, 0.00 to 0.17) with vitamin D supplementation. These findings remained significant in sensitivity analyses for blood pressure, lipid profile, serum PTH, and serum hs-CRP. There was no significant effect of vitamin D supplementation on PWV (SMD = −0.20 ± 0.13 m/s, 95% CI, −0.46 to 0.06, p = 0.14) and AI (SMD = −0.09 ± 0.14%, 95% CI, −0.37 to 0.19, p = 0.52) for vitamin D supplemented groups.

Conclusion: These findings suggest that vitamin D supplementation may act to protect against CVD through improving risk factors, including high blood pressure, elevated PTH, dyslipidemia, and inflammation.

Vitamin D Supplementation, Glycemic Control, and Insulin Resistance in Prediabetics: A Meta-Analysis

Diabetes prevention is a public health priority. Vitamin D supplementation may help prevent the development of diabetes in persons at increased risk. We performed a meta-analysis of controlled clinical trials that assessed glycemic outcome measures among adults at risk for type 2 diabetes, including prediabetes, overweight, or obesity. We searched PUBMED/ MEDLINE, CINAHL, and Google Scholar databases for trials published prior to April 2017. Placebo-controlled clinical trials with random allocation to vitamin D with or without calcium supplementation were selected. Data collection included country, study design, inclusion criteria, sample size, form, and dose of vitamin D, supplementation interval, control group, duration, participant characteristics, comorbidities, baseline and follow-up serum 25-hydroxyvitamin D [25(OH)D] concentration, and available outcome measures [glycosylated hemoglobin (HbA1c), fasting plasma glucose, plasma glucose after 2-hour oral glucose tolerance test, and homeostatic model assessment of insulin resistance (HOMA-IR)]. Data synthesis was conducted using random-effect models (PROSPERO registration no. CRD42017055326). Twenty-eight trials, representing 3848 participants, met the eligibility criteria. Compared with the control group, vitamin D supplementation significantly reduced HbA1c level by -0.48% (95% CI, -0.79 to -0.18), fasting plasma glucose level by -0.46 mmol/L (95% CI, -0.74 to -0.19), and HOMA-IR level by -0.39 (95% CI, -0.68 to -0.11). Subgroup analysis revealed that the effects of vitamin D supplementation on different glycemic measures were influenced by age, calcium coadministration, vitamin D deficiency, serum 25(OH)D level after supplementation, and duration of supplementation. Vitamin D supplementation and improved vitamin D status improved glycemic measures and insulin sensitivity and may be useful as part of a preventive strategy for type 2 diabetes.

Database Analysis of Depression and Anxiety in a Community Sample-Response to a Micronutrient Intervention

Background: Depression and anxiety are common mental health concerns worldwide. Broad-spectrum multi-vitamin/mineral approaches have been found to alleviate a number of psychiatric symptoms. We investigated the effects of a nutrient intervention program, which includes optimizing vitamin D levels, on depression and anxiety outcomes from community-based program. Methods: We evaluated self-reported health measures of depression and anxiety collected as part of a community-based program focused on optimizing overall health through nutritional supplementation, education and lifestyle advice. Results: Data were collected from 16,020 participants, with measures including European Quality of Life Five Dimensions (EQ-5D) and Targeted Symptoms List (TSL) providing self-reported depression and anxiety. More than 56% of participants were identified as having elevated levels of depression and anxiety at baseline as reported on the EQ-5D. After one year in the program, 49.2% (n = 7878) of participants who reported any level of depression or anxiety at baseline reported improvement at follow-up. Of those who reported severe/extreme depression at baseline (n = 829), 97.2% reported improvement after one year. Regression analyses revealed a significant association of improvement in depression and anxiety with higher vitamin D status (>100 nmol/L) and more strenuous physical activity. Conclusion: Overall, people from the general population who suffer from mood and anxiety problems may benefit from improved nutritional status achieved with nutritional supplements.

The Association between Serum 25(OH)D Status and Blood Pressure in Participants of a Community-Based Program Taking Vitamin D Supplements

Background: Vitamin D deficiency is a risk factor for hypertension. Methods: We assessed 8155 participants in a community-based program to investigate the association between serum 25-hydroxyvitamin D (25(OH)D) status and blood pressure (BP) and the influence of vitamin D supplementation on hypertension. Participants were provided vitamin D supplements to reach a target serum 25(OH)D > 100 nmol/L. A nested case-control study was conducted to examine the effect of achieving physiological vitamin D status in those who were hypertensive and not taking BP-lowering medication, and hypertensive participants that initiated BP-lowering medication after program entry. Results: At baseline, 592 participants (7.3%) were hypertensive; of those, 71% were no longer hypertensive at follow-up (12 ± 3 months later). There was a significant negative association between BP and serum 25(OH)D level (systolic BP: coefficient = −0.07, p < 0.001; diastolic BP: coefficient = −0.1, p < 0.001). Reduced mean systolic (−18 vs. −14 mmHg) and diastolic (−12 vs. −12 mmHg) BP, pulse pressure (−5 vs. −1 mmHg) and mean arterial pressure (−14 vs. −13 mmHg) were not significantly different between hypertensive participants who did and did not take BP-lowering medication. Conclusion: Improved serum 25(OH)D concentrations in hypertensive individuals who were vitamin D insufficient were associated with improved control of systolic and diastolic BP.

Effect of a vitamin and mineral supplementation on glycemic status: Results from a community-based program

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Vitamin D and a multivitamin supplement in a natural experiment is described.

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Both vitamin D and the multivitamin were associated with a greater chance of regression to normoglycemia.

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Higher vitamin D levels were associated with better outcomes.

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This simple, inexpensive intervention may have implications for prevention of diabetes.

Aims

Diet is a major risk factor for type 2 diabetes mellitus. As cofactors necessary for enzyme function of all metabolic pathways, vitamins and minerals have the potential to improve glucose metabolism. We investigated the effects of a nutrient intervention program on glycemic status.

Methods

We used a form of natural experiment to compare Pure North program participants (n = 1018) that received vitamin D alone (Vital 1) or vitamin D in combination with other nutrients (Vital 2) during two different time periods. Changes in 25-hydroxyvitamin D [25(OH)D], high-sensitivity C reactive protein (hs-CRP), glycated hemoglobin (HbA1c) and glycemic status were characterized over one and two years.

Results

Serum 25(OH)D concentrations increased significantly in both Vital 1 (to 111  ±  49 nmol/L) and Vital 2 (to 119  ±  52 nmol/L) over one year. HbA1c and hs-CRP were significantly reduced over time in Vital 2. Higher 25(OH)D levels after one year were associated with larger decreases in HbA1c and hs-CRP in Vital 2. At one year, 8% of Vital 2 and 16% of Vital 1 participants progressed from normoglycemia to prediabetes/diabetes, whereas 44% of Vital 2 and 8% of Vital prediabetes/diabetes subjects regressed to normoglycemia.

Conclusions

Vitamin D combined with other nutrients was associated with a reduced risk of progression to diabetes and with an increased rate of reversion to normoglycemia in high risk participants. The results suggest that nutrient supplementation regimes may provide a safe, economical and effective means for lowering diabetes risk. Further examination of this potential via randomized controlled trials is warranted.

Untangling the most probable role for vitamin D3 in autism

Recent studies indicate an important role for vitamin D3 in autism spectrum disorder (ASD), although its mechanism is not completely understood. The most puzzling aspect of ASD is that identical twins, who share identical DNA, do not have 100% concordance rates (∼88% for identical and ∼31% for fraternal twins). These findings provide major clues into the etiology: ASD must involve an environmental factor present in the prenatal milieu that both identical twins are not always exposed to because they do not always share it (i.e., placentas). Combined with the exponential increasing rates of ASD around the world, these observations suggest a contagious disease is probably transferred to the fetus via the placenta becoming infected by a cervical virus. Vitamin D3 boosts immune responses clearing viral infections and increases serotonin and estrogen brain levels. Here we review the different roles and untangle the most probable one vitamin D3 plays in ASD.

The Effect of Improved Serum 25-Hydroxyvitamin D Status on Glycemic Control in Diabetic Patients: A Meta-Analysis

BACKGROUND

Type 2 diabetes is a global health concern, with an increased prevalence and high cost of treatment.

OBJECTIVE

The aim of this systematic review and meta-analysis was to determine the effect of vitamin D supplementation and improved vitamin D status on glycemia and insulin resistance in type 2 diabetic patients.

DATA SOURCE

We searched PUBMED/Medline, Cumulative Index to Nursing and Allied Health, and Cochrane Library (until January 2017).

STUDY SELECTION

Prospective clinical trials were selected evaluating the impact of vitamin D supplementation on glycosylated hemoglobin (HbA1c), serum fasting plasma glucose (FPG), and homeostatic model assessment of insulin resistance (HOMA-IR) in diabetic patients.

DATA EXTRACTION AND SYNTHESIS

We used a random-effects model to synthesize quantitative data, followed by a leave-one-out method for sensitivity analysis. The systematic review registration was CRD42017059555. From a total of 844 entries identified via literature search, 24 controlled trials (1528 individuals diagnosed with type 2 diabetes) were included. The meta-analysis indicated a significant reduction in HbA1c [mean difference: -0.30%; 95% confidence interval (CI): -0.45 to -0.15, P < 0.001], FPG [mean difference: -4.9 mg/dL (-0.27 mmol/L); 95% CI: -8.1 to -1.6 (-0.45 to -0.09 mmol/L), P = 0.003], and HOMA-IR (mean difference: -0.66; 95% CI: -1.06 to -0.26, P = 0.001) following vitamin D supplementation and significant increase in serum 25-hydroxyvitamin D levels [overall increase of 17 ± 2.4 ng/mL (42 ± 6 nmol/L)].

CONCLUSIONS

Vitamin D supplementation, a minimum dose of 100 µg/d (4000 IU/d), may significantly reduce serum FPG, HbA1c, and HOMA-IR index, and helps to control glycemic response and improve insulin sensitivity in type 2 diabetic patients.