Use of a novel vitamin D bioavailability test demonstrates that vitamin D absorption is decreased in patients with quiescent Crohn's disease

High prevalence of vitamin D deficiency in Taiwanese patients with inflammatory bowel disease

Vitamin D deficiency is common in patients with inflammatory bowel disease (IBD). In this study, we aimed to evaluate the prevalence and risk factors of vitamin D deficiency in a Taiwanese IBD cohort. Vitamin D levels were checked in adult patients with IBD who were treated at Changhua Christian Hospital, a medical center in central Taiwan, from January 2017 to December 2023. The risk factors for vitamin D deficiency were evaluated. 106 adult IBD patients were included, including 20 patients with Crohn's disease and 86 with ulcerative colitis. The median age at diagnosis was 39.2 years. The mean vitamin D level was 22.2 ± 8 ng/mL. Forty-five patients (42.5%) had vitamin D deficiency (vitamin D level < 20 ng/mL). Comparing patients with normal vitamin D levels and those with vitamin D deficiency after multivariate adjustment, female sex and early age at diagnosis were identified as statistically significant risk factors. We found a prevalence of 42.5% of vitamin D deficiency in the Taiwanese IBD population. Understanding this issue is essential for teaching patients and doctors about vitamin D deficiency screening and improving patient outcomes.

Development and In Vivo Evaluation of a Novel Vitamin D3 Oral Spray Delivery System

Developing drugs that are highly selective to host tissues but are the least toxic remains one of the most difficult challenges in cancer treatment. Recent studies have shown that tumor cells from a variety of sources can express vitamin D3 receptors and that the response to vitamin D3 and its analogs is prone to growth arrest and cell death. However, conventional vitamin D3 drug formulations lack dose control and cannot target specific cells or tissues. The aim of this study was to prepare vitamin D3 nanospray for inhalation delivery route. This study evaluated the physical properties of the formulation (particle size distribution and biological stability), the total number of sprays per bottle, the spray volume per spray, and the loading variance of the spray. The optimized vitamin D3 spray formula is easy to spray, has fewer drips, and has a fast drying time. It can be stored for 3 months at 37 ± 2 °C temperature, 75 ± 5% relative humidity, and away from light, and can maintain biological stability. This study showed that compared with traditional nasal sprays, the spray has a larger fan angle (82.1 degrees) and beam width (104.88 mm), more symmetrical spray on both sides of the spray column, a faster coverage of the administration site, and a wider range, which is suitable for inhalation delivery routes.

Vitamin D levels in the assessment of Crohn's disease activity and their relation to nutritional status and inflammation

BACKGROUND

Crohn's disease (CD) is frequently associated with malnutrition, inflammation and a deficiency of vitamin D (VD) with the relationships between these symptoms being poorly defined. VD is a modulator of the immune system and is associated with the onset of CD and disease activity. The level of serum VD may have potential in the assessment of CD activity. This study aimed to evaluate the relationships between VD, nutritional status and inflammation, and to identify more accurate VD thresholds.

METHODS

The study included 76 outpatients with CD diagnosed between October 2018 and October 2020 and 76 healthy volunteers. Levels of serum 25(OH)D and nutritional indicators, as well as biochemical and disease activity assessments, were conducted.

RESULTS

Patients with CD and healthy participants were found to differ significantly in their 25(OH)D levels as well in levels of nutritional and inflammatory indicators. The optimal VD cut-off value was found to be 46.81 nmol/L for CD development and 35.32 nmol/L for disease activity. Levels of 25(OH)D were correlated with both nutritional status and inflammation.

CONCLUSIONS

The VD level is likely to be a useful additional tool in the evaluation of CD patients and predicting the disease activity and clinical response. The VD level may relate both to the nutritional status and levels of inflammation in CD patients, and disease progression.

A Scoping Review of Vitamin D for Nonskeletal Health: A Framework for Evidence-Based Clinical Practice

BACKGROUND

Low serum 25-hydroxy-vitamin D [25(OH)D] levels are prevalent worldwide. Although the benefits of vitamin D supplementation have focused on skeletal disorders (eg, rickets, osteomalacia, osteoporosis), emerging evidence for nonskeletal health merits further discussion.

PURPOSE

The purpose of this review was to critically examine the vitamin D supplementation literature pertaining to nonskeletal health to help guide clinicians.

METHODS

A scoping review that included observational studies and randomized clinical trials (RCTs) was performed. Evidence from meta-analyses and individual RCTs are discussed, and controversies and future directions are considered.

FINDINGS

25(OH)D deficiency is a ubiquitous condition associated with multiple nonskeletal diseases, including cardiometabolic (heart disease, diabetes, and kidney disease), immune (HIV/AIDS and cancer), lung (from traditional chronic disorders to coronavirus disease 2019), and gut diseases. Vitamin D deficiency also affects health across the life span (children, pregnant, and elderly), mental illness, and reproduction in both men and women. In contrast, vitamin D supplementation does not necessarily improve major medical outcomes, even when low 25(OH)D levels are treated. Screening for 25(OH)D status remains an important practice, primarily for high-risk patients (eg, elderly, women with osteoporosis, people with low exposure to sunlight). It is reasonable to supplement with vitamin D to treat 25(OH)D deficiency, such that if beneficial nonskeletal health occurs, this may be considered as a coadjutant instead of the central tenet of the disease. Furthermore, optimizing dosing regimens is an important clinical consideration.

IMPLICATIONS

Although 25(OH)D deficiency is prevalent in nonskeletal diseases, there is no uniform evidence that vitamin D supplementation improves major medical outcomes, even when low 25(OH)D levels are corrected. Findings from RCTs warrant caution due to possible selection bias. Overall, vitamin D supplementation must be guided by circulating levels as a reasonable medical practice to correct 25(OH)D deficiency.

The Role of Vitamin D in Autoimmune Thyroid Diseases: A Narrative Review

Vitamin D (VitD) deficiency has garnered significant attention in contemporary medical research. Although the canonical biological activity of VitD manifests itself mainly in the regulation of calcium-phosphorus metabolism, recent studies show that, thanks to the presence of numerous receptors, VitD may also play an important role in regulating the immune system. VitD deficiency has been demonstrated to impact autoimmune disease, coeliac disease, infections (including respiratory/COVID-19), and patients with cancer. Recent studies also show that VitD plays a significant role in autoimmune thyroid diseases (AITDs). Many studies have shown a correlation between low VitD levels and chronic autoimmune thyroiditis - Hashimoto thyroiditis (HT), Graves' disease (GD), and postpartum thyroiditis (PPT). This review article, therefore, describes the current state of knowledge on the role of VitD in AITDs, including HT, GD, and PTT.

The association between vitamin D status and inflammatory bowel disease among children and adolescents: A systematic review and meta-analysis

Aim

Vitamin D deficiency is very common among children with IBD. Since there are conflicting results regarding the association of vitamin D with IBD, we conducted this systematic review to confirm the association of vitamin D with IBD.

Methods

We conducted a systematic search in Scopus, Cochrane Library, Web of Science, PubMed, and Google Scholar to find relevant studies. Articles with cross-sectional and case-control designs that reported the association between vitamin D and IBD among children were included.

Results

Eventually, 9 studies (with 16 effect sizes) reported the mean and SD or the median and the interquartile range of serum vitamin D levels in both subjects with IBD and control subjects. The random effects meta-analysis revealed that subjects with IBD had -1.159 ng/ml (95% CI: -2.783, 0.464) lower serum vitamin D concentrations compared with their healthy counterparts, but this difference was not significant. A total of 14 studies (with 18 effect sizes) with 2,602 participants provided information for the prevalence of vitamin D deficiency or insufficiency in patients with IBD as 44% (95% CI: 0.34-0.54) with significant heterogeneity noted among studies (p < 0.001; I² = 97.31%).

Conclusion

This systematic and meta-analysis study revealed that vitamin D deficiency was associated with IBD. Longitudinal studies should be conducted in the future to confirm our findings. Large randomized controlled trials assessing the doses of supplementation of vitamin D would provide a better understanding of the association between vitamin D and IBD.

Vitamin D: sources, physiological role, biokinetics, deficiency, therapeutic use, toxicity, and overview of analytical methods for detection of vitamin D and its metabolites

Vitamin D has a well-known role in the calcium homeostasis associated with the maintenance of healthy bones. It increases the efficiency of the intestinal absorption of dietary calcium, reduces calcium losses in urine, and mobilizes calcium stored in the skeleton. However, vitamin D receptors are present ubiquitously in the human body and indeed, vitamin D has a plethora of non-calcemic functions. In contrast to most vitamins, sufficient vitamin D can be synthesized in human skin. However, its production can be markedly decreased due to factors such as clothing, sunscreens, intentional avoidance of the direct sunlight, or the high latitude of the residence. Indeed, more than one billion people worldwide are vitamin D deficient, and the deficiency is frequently undiagnosed. The chronic deficiency is not only associated with rickets/osteomalacia/osteoporosis but it is also linked to a higher risk of hypertension, type 1 diabetes, multiple sclerosis, or cancer. Supplementation of vitamin D may be hence beneficial, but the intake of vitamin D should be under the supervision of health professionals because overdosing leads to intoxication with severe health consequences. For monitoring vitamin D, several analytical methods are employed, and their advantages and disadvantages are discussed in detail in this review.

Vitamin D Deficiency and COVID-19: A Biological Database Study on Pathways and Gene-Disease Associations

Vitamin D (VD) is a fat-soluble vitamin, and pivotal for maintaining health. Several genetic markers have been related to a deficient VD status; these markers could confer an increased risk to develop osteoporosis and other chronic diseases. A VD deficiency could also be a determinant of a severe COVID-19 disease. This study aimed to interrogate genetic/biological databases on the biological implications of a VD deficiency and its association with diseases, to further explore its link with COVID-19. The genetic variants of both a VD deficiency and COVID-19 were identified in the genome-wide association studies (GWAS) catalog and other sources. We conducted enrichment analyses (considering corrected p-values < 0.05 as statistically significant) of the pathways, and gene-disease associations using tools, such as FUMA, REVIGO, DAVID and DisGeNET, and databases, such as the Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO). There were 26 and 46 genes associated with a VD deficiency and COVID-19, respectively. However, there were no genes shared between the two. Genes related to a VD deficiency were involved in the metabolism of carbohydrates, retinol, drugs and xenobiotics, and were associated with the metabolic syndrome and related factors (obesity, hypertension and diabetes mellitus), as well as with neoplasms. There were few enriched pathways and disease connections for the COVID-19-related genes, among which some of the aforementioned comorbidities were also present. In conclusion, genetic factors that influence the VD levels in the body are most prominently associated with nutritional and metabolic diseases. A VD deficiency in high-risk populations could be therefore relevant in a severe COVID-19, underlining the need to examine whether a VD supplementation could reduce the severity of this disease.

The Crosstalk between Vitamin D and Pediatric Digestive Disorders

Vitamin D is a cyclopentane polyhydrophenanthrene compound involved mainly in bone health and calcium metabolism but also autophagy, modulation of the gut microbiota, cell proliferation, immune functions and intestinal barrier integrity. The sources of vitamin D include sunlight, diet and vitamin D supplements. Vitamin D3, the most effective vitamin D isoform is produced in the human epidermis as a result of sunlight exposure. Vitamin D undergoes two hydroxylation reactions in the liver and kidney to reach its active form, 1,25-dihydroxyvitamin D. Recent studies highlighted a complex spectrum of roles regarding the wellbeing of the gastrointestinal tract. Based on its antimicrobial effect, it was recently indicated that vitamin D supplementation in addition to standard eradication therapy might enhance H. pylori eradication rates. Moreover, it was suggested that low levels of vitamin D might also be involved in the acquisition of H. pylori infection. In terms of celiac disease, the negative effects of vitamin D deficiency might begin even during intrauterine life in the setting of maternal deficiency. Moreover, vitamin D is strongly related to the integrity of the gut barrier, which represents the core of the pathophysiology of celiac disease onset, in addition to being correlated with the histological findings of disease severity. The relationship between vitamin D and cystic fibrosis is supported by the involvement of this micronutrient in preserving lung function by clearing airway inflammation and preventing pathogen airway colonization. Moreover, this micronutrient might exert anticatabolic effects in CF patients. Inflammatory bowel disease patients also experience major benefits if they have a sufficient level of circulating vitamin D, proving its involvement in both induction and remission in these patients. The findings regarding the relationship between vitamin D, food allergies, diarrhea and constipation remain controversial, but vitamin D levels should be monitored in these patients in order to avoid hypo- and hypervitaminosis. Further studies are required to fill the remaining gaps in term of the complex impact of vitamin D on gastrointestinal homeostasis.

An Update on the Effects of Vitamin D on the Immune System and Autoimmune Diseases

Vitamin D intervenes in calcium and phosphate metabolism and bone homeostasis. Experimental studies have shown that 1,25-dihydroxyvitamin D (calcitriol) generates immunologic activities on the innate and adaptive immune system and endothelial membrane stability. Low levels of serum 25-hydroxyvitamin D (25(OH)D) are associated with an increased risk of developing immune-related diseases such as psoriasis, type 1 diabetes, multiple sclerosis, and autoimmune diseases. Various clinical trials describe the efficacy of supplementation of vitamin D and its metabolites for treating these diseases that result in variable outcomes. Different disease outcomes are observed in treatment with vitamin D as high inter-individual difference is present with complex gene expression in human peripheral blood mononuclear cells. However, it is still not fully known what level of serum 25(OH)D is needed. The current recommendation is to increase vitamin D intake and have enough sunlight exposure to have serum 25(OH)D at a level of 30 ng/mL (75 nmol/L) and better at 40–60 ng/mL (100–150 nmol/L) to obtain the optimal health benefits of vitamin D.

Vitamin D, the immune system, and its relationship with diseases

Background

Vitamin D is classified as an immunomodulatory hormone that is synthesized because of skin exposure to sunlight. It is known to come into play during the regulation of hormone secretion, immune functions, cell proliferation, and differentiation. Its deficiency can cause many diseases and their associated pleiotropic effects. In addition, in relation to its eminent function as regards adaptive immune response and innate immune response, vitamin D level is associated with immune tolerance.

Methods

Literature search prior to May 2021 was conducted through selected websites, including the MEDLINE, Embase, Web of Science, Cochrane Central, www.ClinicalTrials.gov, PubMed, Science Direct, Google Scholar, and EFSA.

Results

Vitamin D is found effective for the regulation of hormone secretion, immune functions, and cell proliferation along with differentiation. Its role as an immune modulator is based on the presence of receptors on many immune cells and the synthesis of its active metabolite from these cells. Vitamin D, an immune system modulator, inhibits cell proliferation and stimulates cell differentiation. A fair number of immune system diseases, encompassing autoimmune disorders alongside infectious diseases, can occur because of low serum vitamin D levels. Supplementation of vitamin D has positive effects in lessening the severity nature of disease activity; there exists no consensus on the dose to be used.

Conclusion

It is figured out that a higher number of randomized controlled trials are essential to evaluate efficacy pertaining to clinical cases, treatment duration, type, and dose of supplementation and pathophysiology of diseases, immune system functioning, and the effect of vitamin D to be administered.

A pilot-randomized, double-blind crossover trial to evaluate the pharmacokinetics of orally administered 25-hydroxyvitamin D3 and vitamin D3 in healthy adults with differing BMI and in adults with intestinal malabsorption

BACKGROUND

Obese and malabsorptive patients have difficulty increasing serum 25-hydroxyvitamin D [25(OH)D] after taking vitamin D supplementation. Since 25(OH)D is more hydrophilic than vitamin D, we hypothesized that oral 25(OH)D supplementation is more effective in increasing serum 25(OH)D concentrations in these patients.

OBJECTIVES

We aimed to investigate the pharmacokinetics of oral 25-hydroxyvitamin D3 [25(OH)D3] and oral vitamin D3 in healthy participants with differing BMI and malabsorptive patients.

METHODS

A randomized, double-blind crossover trial was performed in 6 malabsorptive patients and 10 healthy participants who were given 900 µg of either vitamin D3 or 25(OH)D3 orally followed by a pharmacokinetic study (PKS). After ≥28 d from the first dosing, each participant returned to receive the other form of vitamin D and undergo another PKS. For each PKS, serum vitamin D3 and 25(OH)D3 were measured at baseline and at 2, 4, 6, 8, and 12 h and days 1, 2, 3, 7, and 14. Pharmacokinetic parameters were calculated.

RESULTS

Data were expressed as means ± SEMs. The PKS of 900 µg vitamin D3 revealed that malabsorptive patients had 64% lower AUC than healthy participants (1177 ± 425 vs. 3258 ± 496 ng · h/mL; P < 0.05). AUCs of 900 µg 25(OH)D3 were not significantly different between the 2 groups (P = 0.540). The 10 healthy participants were ranked by BMI and categorized into higher/lower BMI groups (5/group). The PKS of 900 µg vitamin D3 showed that the higher BMI group had 53% lower AUC than the lower BMI group (2089 ± 490 vs. 4427 ± 313 ng · h/mL; P < 0.05), whereas AUCs of 900 µg 25(OH)D3 were not significantly different between the 2 groups (P = 0.500).

CONCLUSIONS

Oral 25(OH)D3 may be a good choice for managing vitamin D deficiency in malabsorption and obesity. This trial was registered at clinicaltrials.gov as (NCT03401541.

Effects of oral vitamin D supplementation on inflammatory bowel disease: a systematic review and meta-analysis

Vitamin D (VitD) is a fat-soluble micronutrient that plays a critical role in inflammatory bowel disease (IBD). Although the effective properties of VitD in anti-inflammatory and immune moderation were reviewed, some important issues still remain uncovered. Considering the practicability and high bioavailability, as a more recommended therapeutic approach, the effects of oral VitD supplementation on IBD remain inconclusive. This study aims to investigate the effect and safety of oral VitD supplementation on IBD patients, which has already been registered on PROSPERO (no. CRD42020165045). A pooled analysis of 17 trials with 1127 patients revealed that as a safety therapeutic strategy, oral VitD supplementation effectively increased the concentration of serum 25-hydroxyvitamin D [weighted mean difference 12.15 ng mL^-1; 95% confidence interval (CI) 9.26, 15.03; I² = 90%] and decreased serum C-reactive protein levels [standard mean difference (SMD) -0.33; 95% CI -0.61, -0.05; I² = 55%], but it did not decrease erythrocyte sedimentation rate levels (SMD 0.35; 95% CI -4.33, 5.03; I² = 57%), disease activity index (SMD -0.13; 95% CI -0.66, 0.39; I² = 84%) and relapse rate (RR 0.59; 95% CI 0.19, 1.86; I² = 79%). These findings suggest that oral VitD supplementation has a role to play in the therapeutic management of IBD. These findings may contribute to public health and clinical dietary guidelines and improve the health of IBD patients.

Factors affecting the fate of β-carotene in the human gastrointestinal tract: A narrative review

Carotenoids and their metabolites play crucial roles in human health such as in immunity, cell differentiation, embryonic development, maintenance of plasma membrane integrity, and gastrointestinal functions, in addition to counteracting night blindness and other eye-related diseases. However, carotenoid bioavailability is highly variable and often low. The bioavailability of β-carotene, among the most frequently consumed carotenoid from the diet, is determined by food matrix related factors such as carotenoid dose, its location in food the matrix, the physical state in food, the presence of other food compounds in the matrix such as dietary fiber, dietary lipids, other micronutrients present such as minerals, and food processing, influencing also the size of food particles, and the presence of absorption inhibitors (fat replacers and anti-obesity drugs) or enhancers (nano-/micro-formulations). However, also host-related factors such as physiochemical interactions by gastrointestinal secretions (enzyme and salts) and other host-related factors such as surgery, age, disease, obesity, and genetic variations have shown to play a role. This review contributes to the knowledge regarding factors affecting the bioavailability of β-carotene (food and host-relegated), as well as highlights in vitro models employed to evaluate β-carotene bioavailability aspects.

Immunologic Effects of Vitamin D on Human Health and Disease

Vitamin D is responsible for regulation of calcium and phosphate metabolism and maintaining a healthy mineralized skeleton. It is also known as an immunomodulatory hormone. Experimental studies have shown that 1,25-dihydroxyvitamin D, the active form of vitamin D, exerts immunologic activities on multiple components of the innate and adaptive immune system as well as endothelial membrane stability. Association between low levels of serum 25-hydroxyvitamin D and increased risk of developing several immune-related diseases and disorders, including psoriasis, type 1 diabetes, multiple sclerosis, rheumatoid arthritis, tuberculosis, sepsis, respiratory infection, and COVID-19, has been observed. Accordingly, a number of clinical trials aiming to determine the efficacy of administration of vitamin D and its metabolites for treatment of these diseases have been conducted with variable outcomes. Interestingly, recent evidence suggests that some individuals might benefit from vitamin D more or less than others as high inter-individual difference in broad gene expression in human peripheral blood mononuclear cells in response to vitamin D supplementation has been observed. Although it is still debatable what level of serum 25-hydroxyvitamin D is optimal, it is advisable to increase vitamin D intake and have sensible sunlight exposure to maintain serum 25-hydroxyvitamin D at least 30 ng/mL (75 nmol/L), and preferably at 40-60 ng/mL (100-150 nmol/L) to achieve the optimal overall health benefits of vitamin D.

Levels of Vitamin D Are Low After Crohn's Disease Is Established But Not Before

BACKGROUND & AIMS

Low serum levels of vitamin D have been associated with Crohn's disease (CD). However, it is unclear whether low vitamin D levels cause CD or CD reduces serum vitamin D.

METHODS

United States military personnel with CD (n = 240) and randomly selected individuals without CD (controls, n = 240) were matched by age, sex, race, military branch, and geography. We measured 25-hydroxyvitamin D in sera 8-3 years (pre-2) and 3 years to 3 months before diagnosis (pre-1) and 3 months before through 21 months after diagnosis (pre-0). We genotyped VDR and GC vitamin D related polymorphisms. We used conditional logistic regression, including adjustments for smoking, season, enlistment status, and deployment, to estimate relative odds of CD according to vitamin D levels and interactions between genetic factors and levels of vitamin D.

RESULTS

Levels of vitamin D before diagnosis were not associated with CD in pre-2 (P trend = .65) or pre-1 samples (P trend = .84). However, we found an inverse correlation between CD and highest tertile of vitamin D level in post-diagnosis samples (P trend = .01; odds ratio, 0.51; 95% CI, 0.30-0.86). Interactions were not detected between vitamin D levels and VDR or GC polymorphisms. We observed an association between VDR Taq1 polymorphism and CD (independent of vitamin D) (P = .02).

CONCLUSIONS

In serum samples from military personnel with CD and matched controls, we found no evidence for an association between CD and vitamin D levels up to 8 years before diagnosis. However, we observed an inverse-association between post-diagnosis vitamin D levels and CD. These findings suggest that low vitamin D does not contribute to development of CD-instead, CD leads to low vitamin D.

Vitamin D levels in IBD: a randomised trial of weight-based versus fixed dose vitamin D supplementation

Objectives: Body weight is one of the factors affecting blood levels of 25-hydroxyvitamin D (25OHD). The aim of this study was to establish whether a vitamin D (vitD) weight-based dosing is more appropriate to a fixed daily dose in patients with inflammatory bowel disease (IBD).Materials/methods: This was an open label randomised trial. Patients with IBD were assigned to receive oral cholecalciferol at a dose of 28 IU/kg (IU/kg) or 2000 IU per day (IU/day) for 12 weeks during winter months. 25OHD plasma levels and other biochemical parameters were measured at baseline and after supplementation period. The primary outcome measure was 25OHD level after a follow-up period.Results: A total of 173 patients were analysed. The mean BMI was 25.5 ± 5.1 and initial mean 25OHD level was 62.7 ± 25.5 nmol/l. A similar increase (9.7 ± 26.9 vs 9.8 ± 26.7 nmol/l) in 25OHD levels occurred both in IU/kg and IU/day group. The proportion of subjects with normal and sub-normal levels following the substitution was comparable irrespective of body weight. The change in 25OHD level correlated positively only with the dose of vitD (p < .001) and negatively with the baseline 25OHD level (p < .001). A sustained 25OHD level of 75 nmol/l corresponds with a calculated daily vitD dose of 2034 IU.Conclusions: Weight-based dosing of vitamin D is not superior to a fixed dose in order to maintain stable 25OHD levels in IBD patients. Cholecalciferol dose of 2,000 IU/day is safe and sufficient during winter period.

Single High-dose Vitamin D3 Supplementation in Pediatric Patients With Inflammatory Bowel Disease and Hypovitaminosis D

OBJECTIVES

The primary aim was to determine the effectiveness of a single high-dose of oral vitamin D3 (stoss therapy) in children with inflammatory bowel disease (IBD) and hypovitaminosis D. Our secondary aim was to examine the safety of stoss therapy.

METHODS

We conducted a randomized, prospective study of 44 patients, ages 6 to 21 years, with IBD and 25-hydroxyvitamin D (25-OHD) concentrations <30 ng/mL. Patients were randomized to receive 50,000 IU of vitamin D3 once weekly for 6 weeks (standard of care, SOC group) or 300,000 IU once (stoss group). Serum 25-OHD levels were obtained at baseline, 4 and 12 weeks. Safety monitoring labs were performed at week 4.

RESULTS

Thirty-nine of 44 enrolled patients (19 stoss, 20 SOC) completed the study. Baseline vitamin D levels were not significantly different between the groups. Stoss therapy resulted in a substantial rise in 25-OHD levels at week 4, equivalent to the weekly regimen (53.6 ± 17.3 vs 54.6 ± 17.5 ng/mL). At week 12, serum 25-OHD levels decreased in both groups, significantly lower in the stoss group, but remained close to 30 ng/mL (29.8 ± 7.1 vs 40.4 ± 11.9 ng/mL, P = 0.04). A significant interaction with treatment group over time was observed (P = 0.0003). At the week-4 time point, all patients who received stoss therapy had normal serum calcium and PTH levels. Eighty percentage of patients preferred stoss therapy to the weekly regimen.

CONCLUSIONS

Stoss therapy was safe and effective in raising 25-OHD in children with IBD commensurate to that of the weekly regimen.

Vitamin D microencapsulation and fortification: Trends and technologies

Today, as per the latest medical reports available, majority of the population throughout globe is facing vitamin D (Vit D) deficiency. Even in sub-tropical countries like India and many others Vit D deficiency is highly prevalent despite the exuberant available sunshine (a major source of Vit D) throughtout the year. The reason could be attributed to an array of factors including socioeconomical, cultural and religious. Further, other than the sunlight, there are very limited sources of Vit D to fulfil the recommended dietary allowance of Vit D (RDA: 400-800 IU per day). A large proportion of Vit D is lost during food processing and storage due to environmental stress conditions such as temperature, pH, salt, oxygen and light. Vita D, an important micronutrient, is essentially required for the prevention of disorders such as neurodegenerative diseases, cardiovascular diseases, cancer etc. in addition to its traditional role in bone metabolism. Therefore, in order to meet the daily requirements of Vit D for human body, WHO has recognized fortification as the most efficient and safest method to address malnutrition. But there are innumerable chellenges involved during food fortification using Vit D as fortificants such as homogeneity into the food matrix, physico-chemical/photochemical degradation, loss during processing and storage, interactions with other components of food matrix resulting into change in taste, texture and appearance thus affecting acceptability, palatability and marketability. Fortification of Vit D into food products especially the ones which have an aqueous portion, is not simple for food technologist. Recent advances in nanotechnology offer various microencapsulation techniques such as liposome, solid-lipid particles, nanostructured lipid carriers, emulsion, spray drying etc. which have been used to design efficient nanomaterials with desired functionality and have great potential for fortification of fortificants like Vit D. The present review is an undate on Vit D, in light of its fortification level, RDA, factors affecting its bioavailability and various microencapsulation techniques adopted to develop Vit D-nanomaterials and their fate in food fortification.

Vitamin D in Inflammatory Bowel Disease: Biological, Clinical and Therapeutic Aspects

BACKGROUND

Vitamin D has an immunoregulatory action in Inflammatory Bowel Disease (IBD) as well as other immune-mediated disorders. Its influence on intestinal permeability, innate and adaptive immunity, and the composition and diversity of the microbiota contribute to the maintenance of intestinal homeostasis. Patients with IBD have a greater prevalence of vitamin D deficiency than the general population, and a possible association between this deficit and a worse course of the disease. However, intervention studies in patients with IBD have proved inconclusive.

OBJECTIVE

To review all the evidence concerning the role of vitamin D as an important factor in the pathophysiology of IBD, review the associations found between its deficiency and the prognosis of the disease, and draw conclusions for the practical application from the main intervention studies undertaken.

METHODS

Structured search and review of basic, epidemiological, clinical and intervention studies evaluating the influence of vitamin D in IBD, following the basic principles of scientific data.

RESULTS

Vitamin D deficiency is associated with disease activity, quality of life, the consumption of social and healthcare resources, and the durability of anti-TNFα biological treatment. Determination of new metabolites of vitamin D, measurement of its absorption capacity and questionnaires about sun exposure could help identify groups of IBD patients with a special risk of vitamin D deficiency.

CONCLUSION

Well-designed intervention studies are needed in IBD, with probably higher objective plasma doses of vitamin D to establish its efficacy as a therapeutic agent with immunomodulatory properties. Meanwhile, vitamin D deficiency should be screened for and corrected in affected patients in order to achieve adequate bone and phosphocalcic metabolism.

Provitamin D3 modulation through prebiotics supplementation: simulation based assessment

Vitamin D is important in multiple health conditions. Vitamin D deficiency is prevalent globally even with exposure to adequate sunlight. Reduction in provitamin D₃ (7-dehydrocholesterol, 7-DHC) is an important cause of vitamin D₃ deficiency. Vitamin supplementation, food fortification, and use of probiotics are some approaches to reduce vitamin D₃ deficiency. This study investigates plausibility of 7-DHC biosynthesis through dietary prebiotics supplementation. Furthermore, it reports mechanistic details and constraints for the biosynthesis using flux balance analysis (FBA) simulations. The FBA simulations using co-metabolism models comprising human host and a resident bacterium (Faecalibacterium prausnitzii or Bacteroides thetaiotamicron) indicated increased flux of 7-DHC with short-chain fructooligosaccharide (scFOS) or inulin supplementation. We observed around 2-fold increase in flux compared to the baseline. Biosynthesis of 7-DHC was primarily modulated through acetate, pyruvate and lactate secreted by the bacterium. We observed diverse mechanisms and dose dependent responses. We extended this assessment to 119 resident bacteria and investigated the metabolites profiles with prebiotics supplementation. In summary, the current study suggests the potential use of applying prebiotics in enhancing 7-DHC biosynthesis. Furthermore, performance of the different gut bacteria with prebiotic supplementation for secreted metabolites profile is reported. These results may be useful to design future clinical studies.

The Association of Disease Activity, BMI and Phase Angle with Vitamin D Deficiency in Patients with IBD

Hypovitaminosis D is frequently present in inflammatory bowel disease (IBD) with a higher incidence in Crohn's disease (CD) than in Ulcerative Colitis (UC). Given the involvement of the alimentary tract, many factors can contribute to hypovitaminosis D. The aim of the study was to investigate the association of disease activity, body mass index (BMI) and phase angle with vitamin D deficiency in patients with IBD. A cross-sectional study was conducted on a cohort of 206 IBD patients (October 2016-September 2018). Of these patients, 32.6% were affected by hypovitaminosis D (CD: 38.6%; UC: 25.6%; p < 0.01). Negative and significant associations (p < 0.01) were found between BMI and vitamin D serum levels both in CD and UC patients. BMI represented a determinant of hypovitaminosis D (Odds Ratio (OR) = 1.12, p < 0.01) only in UC patients; phase angle was associated to hypovitaminosis D in both groups (CD: OR = 0.64, p < 0.05; UC: OR = 0.49, p < 0.01). Results of the present study confirm a higher incidence of hypovitaminosis D in patients with CD than in those with UC, and show that nutritional status plays a crucial role in the incidence of vitamin D deficiency in patients with IBD.

Vitamin D deficiency associated with Crohn's disease and ulcerative colitis: a meta-analysis of 55 observational studies

PURPOSE

To investigate the association of serum levels of 25(OH)D and 1,25(OH)₂D₃ in healthy and non-healthy controls with Crohn's disease (CD) and ulcerative colitis (UC).

METHODS

Three electronic databases: PubMed, EMbase and EBSCOhost CINAHL, were searched for observational studies to measure the relationship between serum levels of vitamin D (VitD) and CD (or UC).

RESULTS

Fifty-five studies were included in the meta-analysis. We found that mean serum 25(OH)D levels in patients with CD were significantly lower than those in healthy controls (MD: - 3.17 ng/mL; 95% CI - 4.42 to - 1.93). Results from the meta-analysis examining 1,25(OH)₂D₃ levels in Crohn's patients revealed higher levels in the CD group than in healthy (MD: 3.47 pg/mL; 95% CI - 7.72 to 14.66) and UC group (MD: 5.05 pg/mL; 95% CI - 2.42 to 12.52). Serum 25(OH)D levels were lower in the UC group than in the healthy control group (MD: - 2.52 ng/mL; 95% CI - 4.02 to - 1.02). In studies investigating the level of 1,25(OH)₂D₃ in UC and healthy control groups, the level of 1,25(OH)₂D₃ in the UC groups were found to be higher than that in the control groups (MD: 3.76 pg/mL; 95% CI - 8.36 to 15.57). However, the 1,25(OH)₂D₃ level in patients with UC was lower than that in CD groups (MD: - 6.71 pg/mL; 95% CI - 15.30 to 1.88). No significant difference was noted between CD patients and UC patients in terms of average serum 25(OH)D levels.

CONCLUSIONS

This study found that VitD levels were inversely related to CD and UC. Serum levels of 25(OH)D were lower in patients with CD and UC than in healthy people, and more than half of the patients had insufficient vitamin D levels. The serum level of 1,25(OH)₂D₃ in both the CD and UC groups was higher than that in healthy people.

Intestinal absorption of vitamin D: a systematic review

Context

Vitamin D is frequently prescribed as a supplement, yet its absorption remains poorly understood.

Objective

This systematic review was performed to evaluate data on mechanisms involved in the intestinal absorption of vitamin D.

Data Sources

PubMed, Embase, and Cochrane Library databases were searched.

Study Selection

The following studies were included: experimental laboratory studies of vitamin D absorption through the enterocyte brush-border membrane; absorption tests that used radiolabeled vitamin D; and clinical trials in adults that investigated a single dose of cholecalciferol or ergocalciferol and reported at least 2 measurements of serum cholecalciferol, ergocalciferol, or 25-hydroxyvitamin D.

Data Extraction

From 2069 articles identified, 46 met the inclusion criteria.

Results

Different methods were employed to evaluate vitamin D absorption. Recent research suggests that vitamin D absorption is not an exclusive simple diffusion process. Vitamin D was better absorbed when it was consumed with fat-containing meals, but absorption also occurred without fat or oily vehicles. Factors that modified cholesterol absorption also altered vitamin D absorption.

Conclusion

Vitamin D is probably absorbed through passive diffusion and a mechanism involving membrane carriers, especially cholesterol transporters, although data remain scarce. Some data suggest that fat, when consumed concomitantly with vitamin D, improves vitamin D absorption.

Comparison of clinical, clinicopathologic, and histologic variables in dogs with chronic inflammatory enteropathy and low or normal serum 25-hydroxycholecalciferol concentrations

Background

The cause of low serum vitamin D concentrations in dogs with chronic inflammatory enteropathy (CIE) is not well understood.

Objective

Improve understanding of pathogenesis of low serum vitamin D concentrations in dogs with CIE by comparing several clinical, clinicopathologic, and histologic variables between CIE dogs with low and normal serum 25‐hydroxyvitamin D concentrations (25[OH]D).

Animals

Fifteen dogs with CIE and low serum 25[OH]D concentrations; 15 dogs with CIE and normal serum 25(OH)D concentrations.

Methods

Prospective cohort study. Clinical and clinicopathologic variables were compared between groups. Correlations between serum 25(OH)D concentration and histopathologic variables were assessed.

Results

Dogs with CIE and low serum 25(OH)D concentrations had higher canine chronic enteropathy clinical activity index scores (P = .003), lower serum α‐tocopherol (P < .001), cholesterol (P < .001), and albumin (P < .001) concentrations and higher serum C‐reactive protein (P = .004) concentrations compared to CIE dogs with normal serum 25(OH)D concentrations. Serum concentrations of vitamin D‐binding protein (VDBP) were not different between groups (P = .91). Duodenal morphologic and inflammatory histopathological scores (P = .002 and P = .004, respectively) and total histopathological scores in duodenum and combined duodenum and ileum negatively correlated with serum 25(OH)D concentration.

Conclusions and Clinical Importance

The pathogenesis of low serum vitamin D concentrations in dogs with CIE is likely multifactorial. Fat malabsorption deserves further study in dogs with low serum vitamin D concentration and CIE. Loss of VDBP does not appear to be an important cause of low serum vitamin D concentration in dogs with CIE.

Bone alterations in inflammatory bowel diseases

Inflammatory bowel diseases (IBDs) are characterized by a multifactorial partially unknown etiology that involves genetic, immunological and environmental factors. Up to 50% of IBD patients experience at least one extraintestinal manifestation; among them is the involvement of bone density which is referred to as metabolic bone disease (MBD), including osteopenia and osteoporosis. Bone alterations in IBDs population appear to have a multifactorial etiology: Decreased physical activity, inflammation-related bone resorption, multiple intestinal resections, dietary malabsorption of minerals and vitamin D deficiency, genetic factors, gut-bone immune signaling interaction, steroid treatment, microbiota and pathogenic micro-organisms interaction, and dietary malabsorption of minerals, that, all together or individually, may contribute to the alteration of bone mineral density. This review aims to summarize the prevalence and pathophysiology of metabolic bone alterations in IBD subjects outlining the main risk factors of bone fragility. We also want to underline the role of the screening and prophylaxis of bone alterations in Crohn’s disease and ulcerative colitis patients and the importance of treating appropriately MBD.

Current evidence for vitamin D in intestinal function and disease

Vitamin D activity is associated with the modulation of a wide variety of biological systems, in addition to its roles in calcium homeostatic mechanisms. While vitamin D is well known to promote gastrointestinal calcium absorption, vitamin D also plays a role in attenuating and/or preventing the progression of several gastrointestinal diseases including Crohn’s disease, ulcerative colitis, and colorectal cancer, and may also play a role in chemotherapy-induced intestinal mucositis. The pro-differentiation, immunomodulatory, and anti-inflammatory effects of vitamin D, which has been reported in numerous circumstances, are key potential mechanisms of action in the prevention of gastrointestinal disorders. While the debate of the effectiveness of vitamin D to treat bone pathologies continues, the clinical importance of vitamin D therapy to prevent gastrointestinal disorders should be investigated given current evidence, using both nutritional and pharmaceutical intervention approaches.

Impact statement

The non-skeletal functions of vitamin D play an important role in health and disease. The anti-inflammatory properties and maintenance of intestinal function fulfilled by vitamin D impact other systems in the body though downstream processing. This review provides insight into the mechanisms underpinning the potential benefits of vitamin D in both maintaining intestinal homeostasis and associated diseased states.

How would serum 25(OH)D level change in patients with inflammatory bowel disease depending on intestinal mucosa vitamin D receptor (VDR) and vitamin D1-α hydroxylase (CYP27B1)?

BACKGROUND/AIMS

To investigate how the serum 25-hydroxyvitamin D (25(OH)D) level change in patients with inflammatory bowel disease (IBD) and investigate the intestinal mucosa vitamin D receptor (VDR) and vitamin D1-α hydroxylase (CYP27B1) expressions.

MATERIALS AND METHODS

A total of 105 patients with IBD were enrolled in the present study, including 49 cases with ulcerative colitis (UC) and 56 cases with Crohn's disease (CD), compared with 45 healthy controls (CON) during the same period by testing the permeability of the intestinal mucosa. The expressions of VDR and CYP27B1 in the intestinal mucosa were detected, so as the serum endotoxin, tumor necrosis factor (TNF)-α, and 25(OH)D levels.

RESULTS

The lactulose and mannitol absorption ratio (LMR) and serum endotoxin and TNF-α levels were significantly higher in the IBD group than in the CON group (p<0.05). The levels of LMR, endotoxin, and TNF-α were higher in the UC group than in the CD group, but 25(OH)D was lower (p<0.05). VDR in the IBD and UC groups was down-regulated when compared with the CON group (p<0.05), but there was no significance between them (p>0.05). CYP27B1 in the IBD and CD groups was significantly up-regulated compared with the CON group (p<0.05), with no significant difference between them (p>0.05).

CONCLUSION

Patients with IBD exhibit vitamin D metabolism imbalance, lower serum 25(OH)D, and lower VDR expression, but higher CYP27B1 expression in the colonic mucosa. However, VDR and CYP27B1 cannot be used to distinguish UC and CD.

A Review of Extraintestinal Manifestations and Complications of Inflammatory Bowel Disease

Extraintestinal manifestations (EIMs) are common in inflammatory bowel disease (IBD), in both Crohn's disease and ulcerative colitis. Almost any organ system can be affected, including the musculoskeletal, dermatologic, renal, hepatopancreatobiliary, pulmonary and ocular systems. However, the musculoskeletal and dermatologic systems are the most commonly involved sites of manifestations. While some manifestations such as peripheral arthritis and erythema nodosum have an association with IBD activity, others such as axial arthropathy, pyoderma gangrenosum and primary sclerosing cholangitis have an independent disease course. This review provides a summary of the most common EIMs in IBD and their prevalence and management.

Comparative effectiveness of vitamin D supplementation via buccal spray versus oral supplements on serum 25-hydroxyvitamin D concentrations in humans: a systematic review protocol

REVIEW QUESTIONS

The questions of this review are.

The effects of two vitamin D regimens on ulcerative colitis activity index, quality of life and oxidant/anti-oxidant status

Background

The optimum dosage for vitamin D supplementation has not yet been elucidated in patients with Ulcerative colitis (UC). The aim of this study was to investigate the effects of two vitamin D regimens in UC patients with vitamin D deficiency.

Methods

In this double blind randomized clinical trial, 50 patients with mild to moderate UC, who met inclusion criteria, received either 1000 or 2000 IU/day of vitamin D (as low dose or high dose group, respectively) for 12 weeks. Serum 25-hydroxy vitamin D (25-OHD) level, total antioxidant capacity (TAC), and Total Oxidant Status (TOS), the inflammatory bowel disease questionnaire − 9 (IBDQ-9) score and the Simple Clinical Colitis Activity Index Questionnaire (SCCAI) score were assessed before and after intervention.

Results

At the end of study, serum 25-OHD levels significantly increased in the high dose group (P < 0.001) and the increase was significantly more than low dose group (6.7 ± 3.8 ng/mL in the high dose group versus 0.2 ± 0.5 ng/mL in the low dose group) (P < 0.001). Serum TOS concentration decreased significantly (− 0.37 ± 0.26) only in the high dose group (P value = 0.023). There was no statistically significant change in serum TAC between two groups during the study. IBDQ-9 mean score significantly increased in high dose group compared to the low dose group (P value = 0.001) and SCCAI score in both groups reduced (− 2.58 ± 2.16 and − 0.9 ± 0.3 in high dose and low dose respectively), while this reduction was significant only in the high dose group (P value ≥0.001).

Conclusion

Our results indicate that 2000 IU daily dose of vitamin D can increase serum 25-OHD concentration, and quality of life, while it reduces disease activity in UC patients with vitamin D deficiency. We recommend assessment of the vitamin D status in all patients with UC because they may benefit from vitamin D therapy.

Vitamin D in inflammatory bowel disease: more than just a supplement

PURPOSE OF REVIEW

The aim of this review is to explore the protective role of vitamin D on the gastrointestinal tract, summarize the epidemiology of vitamin D deficiency in inflammatory bowel disease (IBD), and highlight recent studies examining the impact of low vitamin D and vitamin D supplementation on IBD clinical outcomes.

RECENT FINDINGS

Vitamin D protects the gut barrier by regulating tight junction proteins and inhibiting intestinal apoptosis. Vitamin D enhances innate immunity by inducing antimicrobial peptides and regulates adaptive immunity by promoting anti-inflammatory T cells and cytokines. Vitamin D may also alter the gut microbiota. The prevalence of vitamin D deficiency in IBD is 30-40%. Predictors of vitamin D deficiency in IBD include non-white ethnicity, IBD-related surgery, BMI more than 30, female sex, and pregnancy. Low vitamin D is associated with increased disease activity, inflammation, and clinical relapse. The effect of vitamin D supplementation on IBD clinical outcomes is inconclusive.

SUMMARY

Vitamin D plays a protective role on gut health. Vitamin D deficiency in IBD is prevalent and associated with poor outcomes. The benefits of vitamin D supplementation in IBD is unclear. Measuring novel vitamin D metabolites and vitamin D absorption in IBD patients may help guide future studies.

Topical vitamin D3: A randomized controlled trial (RCT)

OBJECTIVE

The intent of this study was to test the effect of Top-D, a topical Vitamin D preparation, in delivering vitamin D.

METHODS

Five hundred and fifty healthy patients, with vitamin D insufficiency and deficiency were recruited after written informed consent. Demographic data was recorded, adequate history and clinical examination was done to rule out any metabolic diseases. Complete blood picture, serum calcium, phosphorous, Parathormone and 25 Hydroxy-vitamin D3 (25OHD) was carried out before enrollment of the patients. Patients were divided randomly into two groups 350 in study group and 200 in the control group. Patients in the study group were given Top-D (Vitamin D3 gel made from proniosomal technology) to apply daily on the skin. Top-D 1 g contained 5000 IU of vitamin D3. The control group was given 1 g of Aloe vera gel to be applied every day. The two groups had no knowledge to which group they belong. After 4 months serum 25OHD was tested again.

RESULTS

Three hundred and forty five patients in study group and 192 in control group completed the study. The mean age of the patients in the both the groups was 42 years (18-80 years). The pretreatment 25OHD level in the study group was 11.03 ± 4.57 (2-12) ng/l compared to the control group 10.36 ± 4.09 (2-21) and post treatment the levels were 37.17 ± 6.04 (12-54) ng/ml and 10.51 ± 3.5 (2-19) ng/ml (p < 0.001).

CONCLUSION

The results of this study indicate that transdermal route of vitamin D is potentially, safe and can give desired results to raise the vitamin D levels. This route is an alternate route for supplementation of vitamin D which should be utilized.

Vitamin D Status and Its Relation to Inflammatory Markers in Patients with Mild to Moderate Ulcerative Colitis

BACKGROUND

Inflammatory bowel disease (IBD), Crohn’s disease (CD), and Ulcerative colitis (UC) are autoimmune inflammatory diseases of the alimentary tract, which seems to be caused by the interaction of environmental and genetic factors as well as diet and nutritional factors such as vitamin D. The aim of this study was to assess the vitamin D status and its associations with erythrocyte sedimentation rate (ESR), and high-sensitivity C-reactive protein (hs-CRP) as inflammatory markers in patients with UC.

METHODS

In this analytical cross-sectional study 90 patients with mild to moderate UC who were resident of Tehran were assessed. 25(OH)D, parathyroid hormone (PTH), ESR and hs-CRP were measured. Dietary intake was assessed by 3-day 24h diet recall. Statistical analyses were performed using STATA (Version 12).

RESULTS

The average serum 25-OH-vitamin D3 was 33.1 ± 8.3 ng/mL and 38.9% of the patients were vitamin D deficient or insufficient (37.3% of men and 41% of women). No significant correlation between serum 25(OH)D and hs-CRP, ESR, body mass index (BMI), and disease duration was found. There were no significant differences in serum 25(OH)D between men and women. Mean daily dietary vitamin D and calcium intakes were 189.5 Iu (95% CI: 176.0 - 203.1) and 569.5 mg (95% CI: 538.8 - 600.2) respectively.

CONCLUSION

In this cross-sectional study 38.9% of the patients with mild to moderate UC were vitamin D deficient or insufficient and vitamin D level was not correlated to ESR and/or hs-CRP. More studies are needed to investigate the effect of vitamin D in the pathogenesis of UC or as a part of its treatment.

Inadequate sunlight exposure in patients with inflammatory bowel disease

OBJECTIVE

Inadequate sun exposure impairs vitamin D activity and favors low bone density, especially in patients at increased risk for osteoporosis, such as those affected by inflammatory bowel disease (IBD). In this study, sun exposure was investigated in a large series of patients with IBD in a Mediterranean country, Italy, where this risk is considered less likely to occur than in higher latitudes.

METHODS

This is a case-control study of 292 patients with IBD [132 with Crohn's disease (CD) and 160 with ulcerative colitis (UC)], 80 diseased and 540 healthy controls, conducted via a validated questionnaire to quantify sunlight exposure. Data were also compared with controls matched by age and gender.

RESULTS

In total 78 of the 292 patients with IBD had low, 169 had moderate and 45 had high exposure to sunlight, significantly differing from controls (P < 0.001). The 132 patients with CD were more likely to have abnormal levels of sunlight exposure (49 low, 72 moderate and 11 high) than those with UC (29 low, 97 moderate and 34 high) (P < 0.001). The controls were significantly more exposed to sunlight than both men and women with IBD (P < 0.001 and 0.004, respectively).

CONCLUSIONS

IBD patients are significantly less exposed to sunlight than matched controls in Italy, often to an extent that may impair vitamin D activation. Increasing responsible sunlight exposure, thus promoting adequate vitamin D concentrations, may prove beneficial in IBD, in geographical areas in which this risk factor is not generally taken into consideration.

Factors influencing the absorption of vitamin D in GIT: an overview

Vitamin D refers to a group of secosteroid compounds and recognized as the antirachitic vitamin, as it counters rickets, mineral desorption from fully-grown bones (Osteodistrophy), bone, joint disorders, and fragility of bones. On one hand, there is scarcity of vitamin D rich food while on other hand a number of factors negotiate its absorption efficiency in human gastrointestinal tract (GIT). These factors include variations in the physiochemical state of the vitamin D (molecular forms, potency and their physiological linkages), the complexity of food matrix (the amount and type of fatty acids, dietary fibers and presence/absence of vitamin D enhancer and inhibitor), and its interaction of other fat soluble compounds with vitamin D as well as the host-associated factors (age, disease, surgery, obesity, genetic variation etc.). It is hypothesized that the bioavailability of vitamin D in GIT is compromised if there changes within these factors. Present article is intended to review the contribution of these factors anticipated to be influencing vitamin D absorption in GIT.

Vitamin D Status and Bone Mineral Density in Children with Inflammatory Bowel Disease Compared to Those with Functional Abdominal Pain

Low vitamin D has been implicated in reduced bone mineral density (BMD) in children with inflammatory bowel disease (IBD). Our study aimed to evaluate differences in serum 25-hydroxyvitamin D (25[OH]D) and total body less head (TBLH) BMD z-scores in children with Crohn's disease (CD), ulcerative colitis (UC), and those with abdominal pain-related functional gastrointestinal disorder (AP-FGID) as the control group. We also examined the correlation between serum 25(OH)D and TBLH BMD z-score, and factors that affect each of these parameters. A total of 105 children were included and divided into 3 groups: AP-FGID (n = 45), CD (n = 43), and UC (n = 17). Among the 3 study groups, TBLH BMD z-scores were found to be significantly different (0.5 ± 0.8 in CD vs. 0.1 ± 0.8 in UC vs. -0.1 ± 1.1 in FGID; P = 0.037), despite similar levels of serum 25(OH)D. Within each study group, correlation between serum 25(OH)D and TBLH BMD z-score was not observed. Factors found to affect the TBLH BMD z-score were sex (P = 0.018), age (P = 0.005) and serum hemoglobin (P = 0.041), while factors influencing serum 25(OH)D were sex (P = 0.018), CD with reference to AP-FGID (P = 0.020), and serum phosphorus (P = 0.018). Based on our results, vitamin D is a relatively small contributor to bone loss in pediatric IBD and clinicians should consider female sex, older age, and low hemoglobin as risk factors for low BMD in children with IBD.

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

Supplementation by the general public with vitamin D at doses above the Tolerable Upper Level of Intake (UL) is becoming quite common. The objective of the current analysis was to characterize the effect of vitamin D supplementation at doses up to 15,000 IU/d in a community-based program on vitamin D status, calcium homeostasis as well as on kidney, liver and immune function. We evaluated data collected for 3,882 participants in a community program for whom there were blood measurements at program entry and at follow-up within 6-18 months between 2013 and 2015. Participants were supplemented with a wide range of vitamin D doses (1,000 - 15,000 IU/d) aimed at achieving serum 25-hydroxyvitamin D [25(OH)D] levels of at least 100 nmol/L. Serum 25(OH)D concentrations up to 300 nmol/L were achieved without perturbation of calcium homeostasis or incidence of toxicity. Hypercalcemia and hypercalciuria were not related to an increase in 25(OH)D concentrations nor vitamin D dose. To achieve serum 25(OH)D levels >100 nmol/L on average, required vitamin D intakes of 6,000 IU/d for normal Body Mass Index (BMI), 7,000 IU/d for overweight and 8,000 IU/d for obese. Doses of vitamin D in excess of 6,000 IU/d were required to achieve serum 25(OH)D concentrations above 100 nmol/L, especially in individuals who were overweight or obese without any evidence of toxicity. Serum 25(OH)D concentrations up to 300 nmol/L were found to be safe.

Predictors of vitamin D deficiency in inflammatory bowel disease and health: A Mississippi perspective

AIM

To identify the predictors of vitamin D deficiency in patients with and without inflammatory bowel disease (IBD).

METHODS

Patients with ulcerative colitis (UC) or Crohn’s disease (CD) related diagnostic codes who received medical care at University of Mississippi Medical Center between July 2012 and 2015 were identified. After thorough chart review, we identified patients with biopsy proven IBD who had also been tested for serum 25-hydroxyvitamin D [25(OH)D] concentration. We compared these patients to a previously studied cohort of healthy controls who also had vitamin D concentration checked. Logistic regression analysis was performed to determine the association between vitamin d deficiency and UC, CD, race, age, gender and body mass index (BMI).

RESULTS

We identified 237 patients with confirmed IBD. Of these, only 211 had a serum 25(OH)D concentrations available in the medical record. The group of healthy controls consisted of 98 individuals with available serum 25(OH)D concentration. 43% of IBD patients were African American (AA). Patients with CD were more likely to have vitamin D concentration checked. Bivariate analysis showed that AA (51% vs 21%, P = 0.00001), subjects with BMI >30 kg/m² (39% vs 23% P = 0.01) and CD (40% vs 26%, P = 0.04) were more likely to be vitamin D deficient than vitamin D sufficient. Those with Age > 65 were more likely to be vitamin D sufficient (46% vs 15%, P = 0.04). Multiple regression showed that only BMI > 30 kg/m² and AA race are associated with vitamin D deficiency.

CONCLUSION

BMI > 30 kg/m² and AA race are predictive of vitamin D deficiency. Gender, age and diagnosis of IBD are not predictive of vitamin D deficiency.

Role of Vitamin D in Inflammatory Bowel Disease

Vitamin D is a secosteroid hormone that possesses immunomodulatory properties and has been demonstrated to potentially influence inflammatory bowel disease (IBD) pathogenesis and activity. Epidemiologic data have associated vitamin D deficiency with an increased risk of IBD, hospitalizations, surgery, and loss of response to biologic therapy. Conversely, IBD itself can lead to vitamin D deficiency. This bidirectional relationship between vitamin D and IBD suggests the need for monitoring and repletion of vitamin D, as needed, in the IBD patient. This review discusses the role of vitamin D in IBD and provides practical guidance on vitamin D repletion.

Vitamin D regulates the tight-junction protein expression in active ulcerative colitis

OBJECTIVE

Epithelial barrier function is primarily regulated by the tight-junction proteins. Ulcerative colitis (UC) is characterized by Th2 immune response with inflammation and epithelial barrier dysfunction, including an elevation of claudin-2 protein function. Recent studies support an important role of vitamin D in the pathogenesis as well as potential therapy of IBD. Vitamin D deficiency is in fact common in patients with IBD. The aim of the study was to determine whether vitamin D could affect IL-13 and IL-6 levels, and regulate the activity of tight-junction proteins. Claudin-1, -2, -4, and -7 in the inflamed and non-inflamed colonic mucosa of UC patients.

MATERIAL AND METHODS

Biopsies from inflamed and non-inflamed tract of colon and rectum from the same active UC patients were cultured with1,25(OH)2D3. IL-13, IL-6 and the tight-junction proteins level were determined.

RESULTS

Claudin-1 and claudin-2 proteins were up-regulated in active UC. The treatment with 1,25(OH)2D3 decreases the claudin-1 and claudin-2 protein levels in both inflamed and non-inflamed tract. Claudin-4 and claudin-7 proteins were down-regulated and their levels increase after incubation with the 1,25(OH)2D3. When the biopsies were incubated with 1,25(OH)2D3, a decrease in IL-13 and IL-6 levels was registered.

CONCLUSIONS

Our results, indicating the inhibition of cytokine levels and the regulation of claudin-2, claudin-4, and claudin-7 by 1,25(OH)2D3, suggest that vitamin D may represent a potential therapeutic agent for the treatment of active UC.

Vitamin D and the Pathogenesis of Inflammatory Bowel Disease

Vitamin D has traditionally been known for its role in bone metabolism, but emerging evidence has suggested a broader role for vitamin D in immune regulation. Vitamin D deficiency has been associated with the pathogenesis of diverse autoimmune disorders and has similarly been implicated as a contributor to inflammatory bowel disease. In this review, we discuss animal, in vitro, genetic, and epidemiologic studies that have linked vitamin D deficiency with inflammatory bowel disease pathogenesis or severity. Nonetheless, we present the caveat in interpreting these studies in the context of reverse causation: Does vitamin D deficiency lead to gastrointestinal disease, or does gastrointestinal disease (with related changes in dietary choices, intestinal absorption, nutritional status, lifestyle) lead to vitamin D deficiency?

Clinical significance of serum 25OHD level in patients with Crohn's disease

AIM: To detect serum 25OHD levels in patients with Crohn's disease, and to analyze the relationship between serum 25OHD level and clinical parameters of Crohn's disease.

METHODS: Forty-five outpatients or inpatients with Crohn's disease (CD group) and 40 normal controls (NC group) were included in the study. Serum 25OHD levels were measured in all subjects by electrochemiluminescence. Correlation analysis was performed to identify the association between serum 25OHD levels and clinical indices of Crohn's disease. Afterwards, we analyzed the influence of related clinical indices on the level of serum 25OHD.

RESULTS: Serum 25OHD level was significantly lower in the CD group than in the NC group (12.17 ng/mL ± 6.12 ng/mL vs 19.56 ng/mL ± 5.69 ng/mL, P < 0.05, t = 5.738). The detection rate of 25OHD deficiency was significantly higher in the CD group than that of the NC group (86.7% vs 62.5%, P < 0.05, χ² = 6.649). Serum 25OHD level was correlated with BMI (P < 0.05, r = 0.508), CRP (P < 0.05, r = -0.713), ESR (P < 0.05, r = -0.389), duration of exposure to sunshine < 30 min/d (P < 0.05, r = 0.362), active disease (P < 0.05, r = 0.384) and use of remicade (P < 0.05, r = 0.475). Serum 25OHD level was significantly lower in patients with Crohn's disease whose duration of exposure to sunshine was < 30 min/d than in those with a duration of exposure to sunshine > 30 min/d (10.33 ng/mL ± 5.75 ng/mL vs 14.47 ng/mL ± 5.91 ng/mL, P < 0.05, t = 2.371), in patients who did not use remicade than in those who used remicade (8.51 ng/mL ± 3.95 ng/mL vs 14.19 ng/mL ± 6.21 ng/mL, P < 0.05, t = 3.302), and in patients with active disease than in those with an inactive stage (9.36 ng/mL ± 4.43 ng/mL vs 14.05 ng/mL ± 6.44 ng/mL, P < 0.05, t = 2.693).

CONCLUSION: Patients with Crohn's disease have significantly lower serum 25OHD level than healthy people. Disease activity, duration of exposure to sunshine and use of remicade can affect serum 25OHD levels in patients with Crohn's disease.

Vitamin D bioavailability: state of the art

There has been renewed interest in vitamin D since numerous recent studies have suggested that besides its well-established roles in bone metabolism and immunity, vitamin D status is inversely associated with the incidence of several diseases, e.g., cancers, cardio-vascular diseases, and neurodegenerative diseases. Surprisingly, there is very little data on factors that affect absorption of this fat-soluble vitamin, although it is acknowledged that dietary vitamin D could help to fight against the subdeficient vitamin D status that is common in several populations. This review describes the state of the art concerning the fate of vitamin D in the human upper gastrointestinal tract and on the factors assumed to affect its absorption efficiency. The main conclusions are: (i) ergocalciferol (vitamin D2), the form mostly used in supplements and fortified foods, is apparently absorbed with similar efficiency to cholecalciferol (vitamin D3, the main dietary form), (ii) 25-hydroxyvitamin D (25OHD), the metabolite produced in the liver, and which can be found in foods, is better absorbed than the nonhydroxy vitamin D forms cholecalciferol and ergocalciferol, (iii) the amount of fat with which vitamin D is ingested does not seem to significantly modify the bioavailability of vitamin D3, (iv) the food matrix has apparently little effect on vitamin D bioavailability, (v) sucrose polyesters (Olestra) and tetrahydrolipstatin (orlistat) probably diminish vitamin D absorption, and (vi) there is apparently no effect of aging on vitamin D absorption efficiency. We also find that there is insufficient, or even no data on the following factors suspected of affecting vitamin D bioavailability: (i) effect of type and amount of dietary fiber, (ii) effect of vitamin D status, and (iii) effect of genetic variation in proteins involved in its intestinal absorption. In conclusion, further studies are needed to improve our knowledge of factors affecting vitamin D absorption efficiency. Clinical studies with labeled vitamin D, e.g., deuterated or (13)C, are needed to accurately and definitively assess the effect of various factors on its bioavailability.

Prospective, Randomized, Double-Blind, Parallel-Group, Comparative Effectiveness Clinical Trial Comparing a Powder Vehicle Compound of Vitamin D With an Oil Vehicle Compound in Adults With Cystic Fibrosis

BACKGROUND

There is little consensus on the most efficacious vehicle substance for vitamin D supplements. Fat malabsorption may impede the ability of patients with cystic fibrosis (CF) to absorb vitamin D in an oil vehicle. We hypothesized that vitamin D contained in a powder vehicle would be absorbed more efficiently than vitamin D contained in an oil vehicle in patients with CF.

METHODS

In this double-blind, randomized controlled trial, hospitalized adults with CF were given a one-time bolus dose of 100,000 IU of cholecalciferol (D₃) in a powder-based or oil-based vehicle. Serum D₃, 25-hydroxyvitamin D, and parathyroid hormone concentrations were analyzed at 0, 12, 24, and 48 hours posttreatment. The area under the curve for serum D₃ and the 12-hour time point were also assessed as indicators of D₃ absorption.

RESULTS

This trial was completed by 15 patients with CF. The median (interquartile range) age, body mass index, and forced expiratory volume in 1 second were 23.7 (19.9-33.2) years, 19.9 (18.6-22.6) kg/m², and 63% (37%-80%), respectively. The increase in serum D₃ and the area under the curve was greater in the powder group ( P = .002 and P = .036, respectively). Serum D₃ was higher at 12 hours in the powder group compared with the oil group ( P = .002), although levels were similar between groups by 48 hours.

CONCLUSIONS

In adults with CF, cholecalciferol is more efficiently absorbed in a powder compared with an oil vehicle. Physicians should consider prescribing vitamin D in a powder vehicle in patients with CF to improve the absorption of vitamin D from supplements.

Vitamin D status in relation to Crohn's disease: Meta-analysis of observational studies

OBJECTIVES

Inconsistent findings have been published regarding vitamin D status among patients with Crohn's disease (CD) and the association with disease severity. We aimed to perform a meta-analysis evaluating serum 25-hydroxy vitamin D and 1,25 dehydroxyvitamin D among CD patients compared with healthy and non-healthy controls, the prevalence of vitamin D deficiency, and the association with disease.

METHODS

We searched MEDLINE, SCOPUS, EMBASE, and Google Scholar up to March 2015 for observational studies assessing serum vitamin D levels in CD patients. A total of 63 studies were included in the following four meta-analyses: 1) a meta-analysis on the mean difference of 25(OH)D levels in CD patients compared with healthy (number of studies = 27) and non-healthy (n = 25) controls; 2) a meta-analysis on the mean difference of 1,25(OH)2 D3 levels in CD patients compared with healthy (n = 7) and non-healthy (n = 8) controls; 3) a meta-analysis on the prevalence of vitamin D deficiency (n = 34); 4) a meta-analysis on the correlation coefficients between vitamin D status severity of CD (n = 6). Subgroup analysis and meta-regression were used to discover possible sources of between-study heterogeneity.

RESULTS

It was found that CD patients had lower levels of 25(OH)D compared with healthy (-3.99 ng/mL; 95% confidence interval [CI]: -5.91 to -2.08) but not non-healthy controls (-1.07 ng/mL; 95% CI: -2.84 to 0.70). There was also no significant mean difference for 1,25(OH)2 D3 for both healthy and non-healthy controls. Meta-analysis on the prevalence of vitamin D deficiency showed an overall prevalence of 57.7% (95% CI: 0.502-0.649). An inverse association was observed between serum vitamin D and severity of CD (-0.36; 95% CI: -0.48 to -0.24). Meta-regression showed that mean levels of 25(OH)D were decreased 0.09 for each unit change of latitude among CD patients compared with healthy controls (B = -0.09, P = 0.004, I(2) residual = 86.08%).

CONCLUSIONS

We found that patients with Crohn's disease had lower serum 25(OH)D concentrations compared with their healthy counterparts, and more than half of them have hypovitaminosis D. Moreover, there was an inverse correlation between circulating 25(OH)D concentrations and severity of Crohn's disease.

Association Between Inflammatory Bowel Disease and Vitamin D Deficiency: A Systematic Review and Meta-analysis

BACKGROUND

Vitamin D plays a role in several immune-mediated diseases, but its association with inflammatory bowel disease (IBD) is unclear. We conducted a systematic review and meta-analysis to assess the association between IBD and vitamin D deficiency.

METHODS

We searched electronic databases from inception to December 2014 for observational studies reporting the presence of vitamin D deficiency (defined as serum 25-hydroxycholecalciferol [25(OH)D] level of ≤20 ng/mL) in IBD patients and having a control group without IBD. Odds ratios (ORs) were combined using a random-effects model. Meta-regression was performed using latitude as a moderator. Study quality was assessed using the Newcastle-Ottawa scale.

RESULTS

Out of 816 citations, 14 eligible studies were identified, comprising 1891 participants (938 IBD cases and 953 controls). Meta-analysis showed that patients with IBD had 64% higher odds of vitamin D deficiency when compared with controls (OR = 1.64; 95% confidence interval, 1.30-2.08; I = 7%; P < 0.0001). Patients with ulcerative colitis had more than double the odds of vitamin D deficiency when compared with normal controls (OR = 2.28; 95% confidence interval, 1.18-4.41; I = 41%; P = 0.01). Latitude did not influence the association between IBD and vitamin D deficiency (P = 0.34). Generalizability of our results might be limited as we summarized unadjusted ORs, because of nonavailability of adjusted ORs in individual studies.

CONCLUSIONS

IBD is significantly associated with having higher odds of vitamin D deficiency. Well-designed randomized controlled trials and longitudinal studies are needed to further explain the role of vitamin D in IBD pathogenesis and its therapy.