Guidelines for Preventing and Treating Vitamin D Deficiency: A 2023 Update in Poland

Assessment of the maternal key micronutrient supply and its correlation with cord blood parameters in twin pregnancies

Background

Multiple pregnancy constitutes a large metabolic expense, so women with twin pregnancies and neonates born as twins might be at risk for micronutrient deficiencies. Therefore, the aim of the study was to assess the supplementation used and supply with key micronutrients: iron, vitamin B12, folic acid and vitamin D in women with twin pregnancies and the correlations with cord blood indicators.

Methods

Maternal and cord blood samples were collected from 51 patients with twin pregnancies and 102 newborns born from those pregnancies between October 2020 and September 2023. Ferritin, vitamin B12, folic acid and vitamin D metabolites concentrations were measured. Additionally, the patients completed a questionnaire regarding pre-and intragestational supplementation.

Results

Iron, vitamin B12, and vitamin D deficiency were diagnosed in 20.8, 13.7 and 12.5% of women with twin pregnancies, respectively. No maternal folate deficiency was identified. Positive weak to moderate correlations were demonstrated between the concentrations of all studied indicators in the maternal and cord blood. Pregestational folic acid and vitamin D supplementation was associated with higher cord blood levels of folic acid and 3-epi-25(OH)D3, respectively. 25(OH)D3 and total 25(OH)D concentrations were higher in newborns whose mothers had supplemented vitamin D during pregnancy.

Conclusion

The problem of iron, vitamin B12 and vitamin D deficiencies in twin pregnancies is still valid. Pre-and intragestational supplementation, as well as maternal micronutrient supply affect the cord blood composition of twins.

Bifidobacterium longum increases serum vitamin D metabolite levels and modulates intestinal flora to alleviate osteoporosis in mice

The elderly population is prone to osteoporosis, owing to the deterioration of the skin, liver, and kidney functions. Vitamin D (VD) supplementation has a limited effect, and VD deficiency is mostly treated with medication. Several studies have shown that the gut microbiota alters intestinal VD metabolism and that probiotic supplements can influence circulating VD levels. Therefore, in the present study, we screened a strain of Bifidobacterium longum FSHHK13M1 that can increase the level of VD metabolites in the fermented supernatant species in vitro by modeling fecal bacterial fermentation. The results showed that FSHHK13M1 intervention significantly increased the serum levels of 1,25-dihydroxy VD and osteocalcin. It activated the expression of the VDR, OPG, Wnt10b/β-catenin, and Runx2/Osterix pathways and inhibited the expression of RANKL/RANK pathway. Furthermore, there was an enhancement in the quantity of bone trabeculae and the proportion of bone volume. Concurrently, the gut microbiota in mice with osteoporosis exhibited signs of imbalance. FSHHK13M1 intervention increased the relative abundance of specific bacteria, such as Faecalibaculum rodentium, Limosilactobacillus fermentum, Bifidobacterium pseudolongum, and Akkermansia muciniphila. These results suggest that B. longum FSHHK13M1 alleviates retinoic acid-induced osteoporosis symptoms by modulating related genes, regulating the intestinal flora and increasing the level of active VD.IMPORTANCEOsteoporosis is a systemic metabolic disease in which the patient's bone mass decreases for a variety of reasons, and the microstructure of the bone tissue is altered, leading to an increase in bone brittleness and susceptibility to fracture. Osteoporosis is almost always present in the elderly population, and fractures from falls are an important predisposing factor for mortality risk in the elderly population. Supplementation is quite limited for them as they are not able to utilize vitamin D well due to declining liver, kidney, and skin functions. In the present study, a strain of Bifidobacterium longum probiotic was found to increase the levels of the active form of vitamin D and ameliorate osteoporosis. This may play an important role in preventing osteoporosis and reducing fracture risk in the elderly.

Effects of vitamin D3 supplementation on the recovery of hospitalized burn patients: a randomized double-blind controlled trial

BACKGROUND

Burn patients, due to their damaged skin, may not be able to synthesize vitamin D. In this study, we aimed to evaluate the effects of vitamin D supplementation on the recovery of hospitalized burn patients.

METHODS

Fifty-four patients participated in a randomized controlled trial. Eighteen patients were randomly assigned to group C (control, received gelatin soft gel as placebo), 18 patients to group D1 (received 1000 IU/day vitamin D), and 18 patients to group D2 (received 3000 IU/day vitamin D). After supplementation, wound biopsy and blood samples were obtained from the patients. Weight, height, 25(OH)D level, wound healing, scar formation, quality of pain, and blood parameters were evaluated.

RESULTS

There were no significant differences in the serum vitamin D levels between the groups at admission (P = 0.52), and 81.5% of the participants were deficient, with a noteworthy increase during study in supplemented groups (P < 0.001). The Bates-Jensen Wound Assessment Tool demonstrated significant differences in wound healing between the C group and the D1 and D2 groups (P = 0.003), and the supplemented groups experienced greater improvement. The D2 group showed significant differences in thickness and total score on the Vancouver scar scale up to three months after discharge (P = 0.03). Moreover, there was a notable decrease in insulin requirements and the number of injected insulin units in the supplemented groups compared with those in group C (P = 0.006 and P = 0.01, respectively). In addition, shorter hospitalization was observed in group D2 (P = 0.04).

CONCLUSION

Supplementation with vitamin D at doses of 1000 and 3000 IU/day improved wound healing and decreased scar thickness as well as exogenous insulin requirements. Overall, at 3000 IU/day, better results were achieved than at 1000 IU/day.

TRIAL REGISTRATION

This article is registered in 24/04/2020 on the Iranian Randomized Clinical Trials Registry (trial registration number (IRCT, code: IRCT20200420047141N1.

The Impact of Long-Term Parenteral Nutrition on Physical Development and Bone Mineralization in Children with Chronic Intestinal Failure

BACKGROUND

This cross-sectional study aimed to assess growth, body weight, and bone mineralization and to identify predictors of metabolic bone disease (MBD) in children with chronic intestinal failure (CIF) on long-term parenteral nutrition (LPN).

METHODS

Twenty-six children with CIF were evaluated on total parenteral nutrition (PN) for at least three years, and 60 healthy controls were assessed. Measurements included body weight, height, BMI, serum levels of 25-hydroxyvitamin D3 (25-OHD3), calcium (Ca), phosphorus (P), magnesium (Mg), and aluminum (Al), as well as urinary excretion of these elements. Dual-energy X-ray absorptiometry (DXA) and the mid-arm muscle area (MAMA) and mid-arm fat area (MAFA) of the CIF group were estimated.

RESULTS

CIF children had significantly lower height, weight, and BMI Z-scores than controls (p < 0.001). While the median bone mineral density (BMD) Z-score was >-2, 34.7% had L1-L4 Z-scores ≤ -2. Urinary Ca and Al excretion were higher in LPN patients, positively correlating with serum 25-OHD3 levels (r = 0.48). Lower serum Ca, P, and Mg were observed in LPN patients (p < 0.001), and BMC L1-L4 correlated positively with MAMA, MAFA, and BMI.

CONCLUSIONS

The physical development of children who require long-term parenteral nutrition due to intestinal failure is poorer than that of healthy children. Although there are risk factors for bone mineralization disorders in children with intestinal failure, no clinical issues, such as pathological fractures, have been observed.

Investigation of 25-hydroxy vitamin D deficiency prevelance in healthy adults aged 18-65 years in Istanbul, Türkiye

Background

This paper aimed to determine the prevalence of 25-hydroxy vitamin D (25(OH)D) deficiency in healthy adult patients who presented to our hospital in Istanbul province and to present the difference between vitamin 25(OH)D levels by gender, age group, season, and month.

Methods

The vitamin 25(OH)D levels of 9,778 adults who presented to our hospital's internal medicine checkup outpatient clinic between January 2022 and December 2023 were analyzed retrospectively. Individuals with chronic disorders were excluded from the study. The adult patients included in the study were divided into two groups by age (18-50 and 51-65 years). Serum 25(OH)D levels were measured using the electrochemiluminescence immunoassay method. A serum 25(OH)D level was considered deficient if below 20 ng/mL, insufficient if 20-30 ng/mL, and sufficient if above 30 ng/mL. The patients' 25(OH)D levels were investigated by age, gender, season, and month.

Results

After measurement, vitamin D levels were deficient in 57.2% of the patients (n=5,592), insufficient in 28.2% (n=2,756), and sufficient in 14.6% (n=1,430). The mean vitamin D level of the 18-50 age group was significantly lower than that of the group 51-65 age group (p=0.001; p<0.01). The vitamin D levels did not statistically significantly differ by gender (p=0.085, p>0.05). The mean vitamin D levels were 17.99±10.88 ng/mL in winter, 18.11±12.69 ng/mL in spring, 22.08±11.58 ng/mL in summer, and 21.67±10.82 ng/mL in fall. There were statistically significant differences according to the season and month of hospital presentation (p=0.001; p<0.01).

Conclusions

The prevalence of vitamin D deficiency (below 20 ng/mL) in healthy adults aged 18-65 years in Istanbul was 57.2%. That prevalence varied across seasons and months, indicating that sunlight was not used sufficiently. Vitamin D deficiency in Istanbul presents a major problem that needs to be remedied.

Vitamin D: Evidence-Based Health Benefits and Recommendations for Population Guidelines

Vitamin D offers numerous under-recognized health benefits beyond its well-known role in musculoskeletal health. It is vital for extra-renal tissues, prenatal health, brain function, immunity, pregnancy, cancer prevention, and cardiovascular health. Existing guidelines issued by governmental and health organizations are bone-centric and largely overlook the abovementioned extra-skeletal benefits and optimal thresholds for vitamin D. In addition, they rely on randomized controlled trials (RCTs), which seldom show benefits due to high baseline 25-hydroxyvitamin D [25(OH)D] concentrations, moderate supplementation doses, and flawed study designs. This review emphasizes the findings from prospective cohort studies showing that higher 25(OH)D concentrations reduce the risks of major diseases and mortality, including pregnancy and birth outcomes. Serum concentrations > 30 ng/mL (75 nmol/L) significantly lower disease and mortality risks compared to <20 ng/mL. With 25% of the U.S. population and 60% of Central Europeans having levels <20 ng/mL, concentrations should be raised above 30 ng/mL. This is achievable through daily supplementation with 2000 IU/day (50 mcg/day) of vitamin D3, which prevent diseases and deaths. Furthermore, a daily dose between 4000 and 6000 IU of vitamin D3 to achieve serum 25(OH)D levels between 40 and 70 ng/mL would provide greater protection against many adverse health outcomes. Future guidelines and recommendations should integrate the findings from observational prospective cohort studies and well-designed RCTs to improve public health and personalized care.

Association between cardiovascular health and serum vitamin D and its interaction with prediabetes and diabetes

BACKGROUND

Prediabetes and diabetes are common and serious public health problems, and high blood glucose can lead to serious cardiovascular complications. The purpose of this article was to explore the link between CVH levels and the incidence of prediabetes and diabetes in people over 20 years old, and whether serum vitamin D status could alter this relationship.

MATERIALS AND METHODS

Data from six consecutive cycles of the NHANES database from 2007 to 2018 were combined and eligible participants were aged ≥20 years. After excluding missing data, a total of 19,992 subjects were enrolled in the study. Significant risk factors for prediabetes and diabetes were analyzed using univariate and multivariate logistic regression. Exploring the interaction of VD and CVH on prediabetes and diabetes based on multifactorial regression analysis.

RESULTS

The prevalence of prediabetes among all participants was 36.15% and the prevalence of diabetes was 16.39%. CVH and vitamin D levels are influential factors in prediabetes and diabetes, and are negatively associated with the risk of developing prediabetes and diabetes. Compared with normoglycemia, poorer CVH and vitamin D deficiency only had a synergistic multiplicative interaction on the development of diabetes, and no significant interaction was observed for the development of prediabetes. Compared with prediabetes, poorer CVH and vitamin D deficiency still had a synergistic additive interaction on the development of diabetes.

CONCLUSIONS

Although the cross-sectional study only determines the association and does not prove causality, the current results can be used to prompt people to improve their lifestyle and risk factors to prevent prediabetes or diabetes through higher CVH and adequate Vitamin D.

Comparative Analyses of the Safety Profiles of Vitamin D Receptor Agonists: A Pharmacovigilance Study Based on the EudraVigilance Database

Background/Objectives: Vitamin D receptor (VDR) agonists are commonly used in clinical practice for their roles in calcium regulation and potential benefits in various diseases. However, their safety profiles, particularly for compounds available as food supplements, remain underexplored in real-world settings. This study aimed to analyze the safety profiles of VDR agonists using the EudraVigilance database, focusing on adverse drug reactions (ADRs) reported between 1 January 2004 and 23 June 2024. Methods: Data for ten VDR agonists were collected, de-duplicated, and analyzed to identify specific safety signals. Risk factors for specific ADRs were assessed using multiple logistic regression. Results: This study analyzed 5,369,581 reports in the EudraVigilance system, from which 17,947 reports (0.33%) involving 80,050 ADRs were linked to VDR agonists. The most-reported drugs were cholecalciferol (12,944 cases) and calcitriol (1355 cases). Serious ADRs were more prevalent with paricalcitol, alfacalcidol, and calcitriol than with cholecalciferol (p < 0.05). Hypercalcemia was a hallmark ADR for all VDR agonists, with the highest risk linked to dihydrotachysterol (ROR = 5668; 95%CI = 3332 to 9641; p < 0.0001), alfacalcidol (ROR = 965.7; 95%CI = 843.6 to 1106; p < 0.0001), and calcitriol (ROR = 726.0; 95%CI = 634.6 to 830.5; p < 0.0001). Logistic regression highlighted dehydration, overdose, and concomitant administration of calcium salts as major predictors of hypercalcemia. The co-administration of multiple VDR agonists was also found to increase hypercalcemia risk. However, the disproportionality analysis showed that only active VDR agonists (e.g., calcitriol, alfacalcidol) were associated with severe complications like renal and urinary disorders and cardiac issues due to hypercalcemia. Natural precursors (cholecalciferol, ergocalciferol) were more often linked to non-calcemic ADRs such as gastrointestinal symptoms, which were more prevalent in infants and children compared to adults. Conclusions: The safety profiles of VDR agonists differ significantly between compounds. Active derivatives require close monitoring for serious calcemia-related complications, whereas cholecalciferol is associated with less severe ADRs, primarily in at-risk populations. These findings highlight the need for targeted safety monitoring and further research into the real-world uses of VDR agonists.

Mindful Eating, BMI, Sleep, and Vitamin D: A Cross-Sectional Study of Cypriot and Greek Adults

BACKGROUND

Obesity and related health challenges remain significant concerns in Cyprus and Greece. Mindful eating (ME) has emerged as a behavioral approach to address these issues, yet its relationship with BMI, vitamin D levels, and sleep duration in Mediterranean populations is underexplored.

OBJECTIVES

This study aimed to examine associations between ME subcategories (Awareness, Distraction, Disinhibition, Emotional, and External Cues), BMI, vitamin D levels, and sleep duration among Cypriot and Greek adults across two cohorts.

METHODS

A cross-sectional design was employed with data collected in 2022 (N1 = 438) and 2023 (N2 = 174). Participants completed the validated Cyprus Mindful Eating Questionnaire (CyMEQ). Vitamin D levels, sleep duration, and BMI were self-reported. Statistical analyses included Mann-Whitney U Tests for ME subcategory comparisons, chi-square tests for categorical variables, and Spearman correlations to examine associations.

RESULTS

Significant differences were found between cohorts in ME subcategories, with N1 scoring higher in Awareness [Median (IQR): 2.60 (2.20-3.00) vs. 2.00 (1.80-2.30), p = 0.02], Disinhibition [2.70 (2.50-3.00) vs. 2.50 (2.20-2.70), p = 0.03], and External Cues [2.50 (2.10-2.90) vs. 2.10 (1.80-2.50), p = 0.01]. ME scores were negatively correlated with BMI (r = -0.25, p = 0.01) and positively associated with vitamin D levels and sleep duration. Differences in vitamin D supplementation practices were observed across groups; however, these differences did not reach statistical significance (p = 0.07).

CONCLUSIONS

ME behaviors, particularly Awareness and Disinhibition, are associated with BMI, highlighting their potential in obesity management. The interplay between ME, vitamin D, and sleep underscores the need for integrative health interventions in Mediterranean populations.

Effects of different supplements on Hashimoto's thyroiditis: a systematic review and network meta-analysis

Clinicians often consider the use of dietary supplements to assist in lowering thyroid autoantibody titres in patients with Hashimoto's thyroiditis (HT). Currently, different supplements differ in their ability to reduce autoantibody levels. The purpose of this article is to compare the ability of different supplements to lower autoantibody titres and restore TSH levels through a systematic literature review. We obtained information from the PubMed, Web of Science, Embase, and Cochrane databases, as well as the China National Knowledge Infrastructure (CNKI). Selected studies included those using selenium, Vitamin D, Myo-inositol, and Myo-inositol in combination with selenium for the treatment of HT patients with euthyroidism. These data were combined using standardised mean differences (SMDs) and assessed using a random effects model. A total of 10 quantitative meta-analyses of case-control studies were selected for this meta-analysis. Compared to the placebo group, the use of selenium supplements was able to significantly reduce the levels of thyroid peroxidase autoantibodies (TPOAb) (SMD: -2.44, 95% CI: -4.19, -0.69) and thyroglobulin autoantibodies (TgAb) (SMD: -2.76, 95% CI: -4.50, -1.02). During a 6-month treatment, the use of Myo-inositol, Vitamin D alone, and the combination of selenium, and Myo-inositol did not effectively reduce TPOAb (Myo-inositol: SMD:-1.94, 95% CI: -6.75, 2.87; Vitamin D: SMD: -2.54, 95% CI: -6.51,1.42; Se+Myo-inositol: SMD: -3.01, 95% CI: -8.96,2.93) or TgAb (Myo-inositol: SMD:-2.02, 95% CI: -6.52, 2.48; Vitamin D: SMD: -2.73, 95% CI: -6.44,0.98; Se+Myo-inositol: SMD: -3.64, 95% CI: -9.20,1.92) levels. Therefore, we recommend that patients with HT(Hashimoto's Thyroiditis) be given an appropriate amount of selenium as an auxiliary treatment during standard-of-care treatment.

Vitamin D-Do Diet Recommendations for Health Remain Strong?

How will the scientific community and authoritative bodies define future nutritional requirements for vitamin D? At the International Symposium on Nutritional Aspects of Musculoskeletal Health, the authors debated the strength of current evidence for setting vitamin D intake recommendations from diet: the positive side of the strength of the evidence (PRO) suggests there is a physiological requirement for vitamin D and the opposing view (CON) that in light of negative results from large, recent trials, particularly those with fractures and bone health outcomes, we are left rudderless. Should we provide recommendations based on empiric treatment of vitamin D for most groups and conditions? It is becoming increasingly evident that vitamin D plays a role in many physiological functions and processes associated with long-term human health; however, to what extent are these benefits apparent beyond what is needed for adequate nutritional status, measured as serum 25-hydroxyvitamin D levels, for active calcium absorption? The meeting attendees voted for the PRO vs. CON position at the end of the session.

Prevalence of Vitamin D Deficiency Among Healthy Young Adults at Kuwait University

OBJECTIVE

 This study aims to investigate the prevalence of vitamin D deficiency among healthy young medical and dental students at Kuwait University.

METHODS

This cross-sectional study included a total of 201 medical and dental students (male = 99; female = 102) at Kuwait University. Blood samples were collected to assess 25-hydroxyvitamin D (25(OH)D) by electrochemiluminescence (ECL) immunoassay, and a questionnaire was distributed to address related qualitative data. P-values less than 0.05 were considered significant.

RESULTS

Vitamin D deficiency (<50 nmol/L) was reported in 171 (85.1%) of the participants. A total of 17 (8.5%) participants exhibited insufficient vitamin D (50.1-75 nmol/L), and only 13 (6.5%) students had optimal vitamin D (>75 nmol/L). According to gender, vitamin D deficiency was more common in male students (89, 89.9%) compared to females (82, 80.4%). Vitamin D levels for students in the clinical academic years (sixth and fifth years) were significantly higher (P < 0.001) compared to the non-clinical years (fourth, third, and second years).

CONCLUSION

 The prevalence of vitamin D deficiency was very high among medical and dental students of Kuwait University. The students with high academic years suffered more from vitamin D deficiency.

Vitamin D Controversies in the Laboratory Medicine: A Review of Clinical Guidelines and Recommendations

A narrative review of the main guidelines and recommendations published from 2011 up to date about the status of vitamin D deficiency has been carried out. The objective of this review is to discuss the origin of the controversy about the status of this entity, as well as the evolution of the methodological aspects and clinical situations that require vitamin D screening. The results obtained indicate that the criteria defining vitamin D status, according to two studies published in 2011, the Institute of Medicine (IOM) recommendations and the Endocrine Society (ES) guidelines, regardless the affected population. Concerning the methodology used, progress has been made thanks to the Vitamin D Standardization Program (VDSP), although the most recent results from the external Vitamin D External Quality Program Assessment Scheme (DEQAS) indicate that there is still a significant bias among the different immunoassays available. In relation to the criteria for screening, an agreement is observed in the most recent publications.

Sex-specific effects of a Mediterranean diet on lower limb bone strength in Polish children

Lifestyle factors have the potential to influence bone health in various ways, whether positively or negatively. As osteoporosis is believed to originate in early years, it is therefore essential to indicate factors that may positively affect bone health during childhood. The aim of our study was to investigate the effects of early and current diet, vitamin D supplementation, and BMI z-score on bone properties in a group of children aged 3-7 years. A cross-sectional sample of 205 preschoolers and their parents participated in the study. Dietary assessment was made using a modified version of the Polish-adapted Mediterranean Diet score (MVP-aMED) on the basis of the data from food frequency questionnaire (FFQ), filled out by the parents. Quantitative ultrasound (QUS) was used in the assessment of bone properties. In the sex-stratified analysis, significant associations were observed between MVP-aMED score (β = 0.193, 95 % CI: 0.005, 0.237; p = 0.04), BMI z-score (β = -0.318, 95 % CI: -1.455, -0.039; p = 0.04) and QUS z-score, exclusively among girls. After adjustment, only the relationship with diet remained significant (β = 0.209, 95 % CI: 0.007, 0.255; p = 0.04), suggesting that a higher adherence to the Mediterranean Diet may be associated with better bone properties in girls aged 3-7 years old. Our results emphasize the importance of fostering healthy dietary habits and maintaining proper weight in children in order to promote optimal bone development.

Vitamin D deficiency in Ukraine: A multicentre cross-sectional study

Background

Available epidemiological data on vitamin D status in the Ukrainian population are limited.

Objective

The aim of this study is to investigate the prevalence of vitamin D deficiency in Ukraine.

Methods

This multicentre cross-sectional study included a total of 11,462 participants: 1530 children with a median age 10 years, (IQR 6-14) and 56.21 % of them were female; 9932 adults with a median age of 36 years (IQR 26-48) and 78.72 % of them were female. Serum 25-hydroxyvitamin D (25(OH)D) levels were measured once by chemiluminescent immunoassay (UniCel DxI 800 Access Immunoassay System, Beckman Coulter Inc., USA) in the period of January-December 2021 in Kyiv and Kyiv Oblast. The cut-offs were: vitamin D deficiency, <50 nmol/L; moderate deficiency, 25-<50 nmol/L; severe deficiency, <25 nmol/L; vitamin D insufficiency, 50-<75 nmol/L; vitamin D sufficiency, 75-<250 nmol/L; optimal concentration, 75-<125 nmol/L; increased levels, 125-<250 nmol/L; and toxicity, ≥250 nmol/L.

Results

The median 25(OH)D level was 65.4 nmol/L (IQR 49.5-85.6) among all participants, severe vitamin D deficiency was recorded in 2.9 % of participants (95 % CI: 2.6-3.2), moderate deficiency in 23 % (95 % CI: 22-24), and vitamin D insufficiency in 37 % (95 % CI: 36-38).Prevalence of vitamin D deficiency in group 1-17 years was 23.5 % (95 % CI: 21-26). We did not find vitamin D deficiency in children aged 1-2 years; however toxic levels were recorded in 4.2 % of the children in this age group (95 % CI: 1.4-9.6). Among the adults (≥18 years old), prevalence of vitamin D deficiency was 26 % (95 % CI: 25-27).

Conclusion

Vitamin D deficiency and insufficiency are common in Ukraine.

Integrating Endocrine, Genomic, and Extra-Skeletal Benefits of Vitamin D into National and Regional Clinical Guidelines

BACKGROUND/OBJECTIVES

Vitamin D is essential for bone health, immune function, and overall well-being. Numerous ecological, observational, and prospective studies, including randomized controlled clinical trials (RCTs), report an inverse association between higher serum 25-hydroxyvitamin D [25(OH)D; calcifediol] levels in various conditions, including cardiovascular disease, metabolic disorders such as diabetes and obesity, susceptibility to infection-related complications, autoimmune diseases, and all-cause mortality.

RESULTS

Vitamin D operates through two distinct systems. The endocrine system comprises the renal tubular cell-derived circulatory calcitriol, which primarily regulates calcium homeostasis and muscular functions. In contrast, intracellularly generated calcitriol in peripheral target cells is responsible for intracrine/paracrine system signaling and calcitriol-vitamin D receptor-mediated genomic effects. Government-appointed committees and health organizations have developed various clinical practice guidelines for vitamin D supplementation and management. However, these guidelines heavily relied on the 2011 Institute of Medicine (IoM) report, which focused solely on the skeletal effects of vitamin D, ignoring other body systems. Thus, they do not represent maintaining good overall health and aspects of disease prevention. Additionally, the IoM report was intended as a public health recommendation for the government and is not a clinical guideline.

DISCUSSION

New country- and regional-specific guidelines must focus on healthy nations through disease prevention and reducing healthcare costs. They should not be restricted to bone effect and must encompass all extra-skeletal benefits. Nevertheless, due to misunderstandings, medical societies and other governments have used faulty IoM report as a foundation for creating vitamin D guidelines. Consequently, they placed disproportionate emphasis on bone health while largely overlooking its benefits for other bodily systems, making current guidelines, including 2024, the Endocrine Society less applicable to the public. As a result, the utility of published guidelines has been significantly reduced for clinical practice and RCTs that designed on bone-centric are generate misleading information and remain suboptimal for public health and disease prevention.

CONCLUSIONS

This review and its recommendations address the gaps in current vitamin D clinical practice guidelines and propose a framework for developing more effective, country and region-specific recommendations that capture the extra-skeletal benefits of vitamin D to prevent multiple diseases and enhance public health.

High Doses of Vitamin D and Specific Metabolic Parameters in Type 2 Diabetes Patients: Systematic Review

Background/Objectives: Type II diabetes mellitus (T2DM) is recognized as a condition of mild chronic inflammation, marked by increased levels of acute-phase proteins and various inflammatory indicators. These inflammatory substances, along with inflammation of adipose tissue and the secretion of adipocytokines, can contribute to insulin resistance and β cell dysfunction. By influencing both innate and adaptive immunity, vitamin D can inhibit the production of inflammatory cytokines and help mitigate the low-grade chronic inflammation associated with T2DM. Several strategies have been proposed to increase vitamin D levels effectively and safely, but the recent and strong ones have common tactics. Short-term high doses increase the level acutely, and long-term lower doses maintain sufficient levels. Methods: The aim of our work was to determine and verify the effectiveness of high doses of vitamin D to safely increase its level in patients with type 2 diabetes mellitus, as well as the effect of these doses on selected metabolic parameters. Data from 20 studies (vitamin D group n = 612, and control group n = 592) regarding the influence of vitamin D supplementation with doses above 4000 IU on serum 25(OH)D, fasting blood glucose (FBG), hemoglobin A1c (HbA1c), blood pressure, serum calcium, and parathormone were pooled. Results: Vitamin D supplementation significantly improved serum 25(OH)D levels, with an average increase after intervention versus baseline at 177.09%. Our studies suggest that vitamin D supplementation may benefit various parameters in T2DM patients, including glycemic control, blood pressure, and PTH levels. Conclusions: Vitamin D supplementation may have beneficial effects on various parameters in type 2 diabetes patients, including glycemic control, blood pressure, and parathormone levels. However, the results are only sometimes consistent across all studies. Further examination is needed.

Nutrition, hydration and supplementation considerations for mountaineers in high-altitude conditions: a narrative review

Staying and climbing in high mountains (>2,500 m) involves changes in diet due to poor access to fresh food, lack of appetite, food poisoning, environmental conditions and physiological changes. The purpose of this review is to summarize the current knowledge on the principles of nutrition, hydration and supplementation in high-altitude conditions and to propose practical recommendations/solutions based on scientific literature data. Databases such as Pubmed, Scopus, ScienceDirect and Google Scholar were searched to find studies published from 2000 to 2023 considering articles that were randomized, double-blind, placebo-controlled trials, narrative review articles, systematic reviews and meta-analyses. The manuscript provides recommendations for energy supply, dietary macronutrients and micronutrients, hydration, as well as supplementation recommendations and practical tips for mountaineers. In view of the difficulties of being in high mountains and practicing alpine climbing, as described in the review, it is important to increase athletes' awareness of nutrition and supplementation in order to improve well-being, physical performance and increase the chance of achieving a mountain goal, and to provide the appropriate dietary care necessary to educate mountaineers and personalize recommendations to the needs of the individual.

Hemodialysis Patients May Benefit from Cholecalciferol Treatment Targeting High Level of 25(OH)D

(1) Background and Objectives: Vitamin D is implicated in the pathogenesis of Chronic Kidney Disease-Mineral and Bone Disorder (CKD-MBD) in hemodialysis (HD) patients, including the development of secondary hyperparathyroidism (SHP). While cholecalciferol supplementation is recommended for vitamin D deficiency correction, its impact on CKD-MBD remains inconsistent. The aim of this observational prospective study was to assess the effect of cholecalciferol in achieving high-normal serum 25-hydroxycholecalciferol (25(OH)D > 75 ng/mL) levels and its impact on CKD-MBD biochemical markers, including 1,25-dihydroxycholecalciferol (1,25(OH)2D) and parathormone (PTH) in HD patients. The study also evaluated the maintenance dosage required to sustain 25(OH)D levels within the 50-75 ng/mL range. (2) Materials and Methods: A total of 22 HD patients with baseline 25(OH)D levels 30-50 ng/mL received cholecalciferol (70,000 IU/week) to achieve the target serum 25(OH)D > 75 ng/mL. Baseline data on calcium, phosphate, 1-84 PTH, 25(OH)D, and 1,25(OH)2D serum levels were compared with the data when 25(OH)D > 75 ng/mL was targeted or when the highest 25(OH)D levels were noted. (3) Results: Cholecalciferol significantly improved vitamin D status in HD patients, with 73% reaching the target 25(OH)D level >75 ng/mL in a median time of 7.5 weeks, with a median total dose of 525,000 IU. This was associated with a significant rise in 1,25(OH)2D, decrease in 1-84 PTH, and no significant effect on calcium and phosphate levels. The median maintenance dose of cholecalciferol was established at 30,000 IU/week. (4) Conclusions: The findings support the use of cholecalciferol targeting high normal 25(OH)D levels to improve biochemical markers of CKD-MBD in HD patients.

Craniotabes in Newborns and the Role of Maternal Vitamin D Deficiency: A Case Series

Craniotabes is characterized by the softening of skull bones in newborns. It can be associated with conditions like rickets, congenital syphilis, and osteogenesis imperfecta. In otherwise healthy newborns, craniotabes is often linked to in utero vitamin D deficiency. We report four cases of term infants diagnosed with craniotabes at birth. For all cases, laboratory tests confirmed vitamin D deficiency with serum 25-hydroxyvitamin D levels below 20 ng/mL, alongside maternal vitamin D deficiency. While three cases showed no complications, one newborn had a skull fracture and a neonatal stroke. All infants were supplemented with oral cholecalciferol, resulting in the normalization of serum 25-hydroxyvitamin D levels and resolution of the skull softening. These cases highlight the critical role of maternal vitamin D levels in fetal bone development and the potential risks of its deficiency. Although craniotabes associated with maternal vitamin D deficiency is a known condition among neonatologists, these cases help to increase awareness of this diagnosis. We highlight the need for thorough clinical examination, along with complementary diagnostic tests, to identify any related complications.

How Follow-Up Period in Prospective Cohort Studies Affects Relationship Between Baseline Serum 25(OH)D Concentration and Risk of Stroke and Major Cardiovascular Events

Background/Objectives: Prospective cohort studies are useful for studying how biomolecular status affects risk of adverse health outcomes. Less well known is that the longer the follow-up time, the lower the association (or "apparent effect") due to "regression dilution". Here, we evaluate how follow-up interval from baseline to "event" affects the relationship between baseline serum 25-hydroxyvitamin D [25(OH)D] concentration and the later incidence of stroke and major cardiovascular events (MACEs). Methods: Findings for the relative risk (RR) of stroke and MACEs with respect to serum 25(OH)D concentrations at baseline from prospective cohort studies were plotted against mean follow-up time. Fifteen studies from mainly European countries and the United States were used for stroke and nine studies for MACEs. Linear regression analyses were used to study data for follow-up periods of up to 10 years and for more than 10 years. Results: For stroke, the linear regression fit for 1-10 years is RR = 0.34 + (0.065 × follow-up [years]), r = 0.84, adjusted r2 = 0.67, p < 0.001. No significant variations in association were found for studies with follow-up periods of 10-20 years. For MACEs, the linear fit for 1-8.1 years is RR = 0.61 + (0.055 × follow-up [years]), r = 0.81, adjusted r2 = 0.59, p = 0.03. Discussion: The shorter the follow-up period, the greater the apparent effect of better vitamin D status in reducing risk of stroke and MACEs. In addition, the apparent effect of higher 25(OH)D concentration found for the shortest follow-up time is more than twice as great as the estimate based on average follow-up intervals for all studies. Mechanisms have been found to explain how higher serum 25(OH)D concentrations could reduce risk of stroke and MACEs. Randomized controlled trials have not shown that vitamin D supplementation significantly reduces risk of either stroke or MACEs, probably because risk of both outcomes increases rapidly below 15 ng/mL (38 nmol/L) and it is difficult in Western developed countries to enroll enough participants with concentrations that low. Nonetheless, vitamin D's role in reducing risk of stroke and MACEs could be considered causal on the basis of an evaluation of the evidence using Hill's criteria for causality in a biological system. Conclusions: Serum 25(OH)D concentrations above 20 ng/mL are associated with significantly reduced risk of stroke and MACEs prospectively and in an apparent causal manner. Raising serum 25(OH)D concentrations to >20 ng/mL should, therefore, be recommended for everyone likely to be at risk for stroke or MACEs and indeed in the general population.

Predictors of Dietary Supplement Use Among Children Attending Care and Educational Institutions in Krakow, Poland

BACKGROUND/OBJECTIVES

Socioeconomic status and parental lifestyle influence dietary behaviors, including the administration of oral dietary supplements in children. The aim of this study was to evaluate the effects of selected health, dietary, and sociodemographic factors on the use of dietary supplements by children.

METHODS

In this cross-sectional observational study, a diagnostic survey based on the computer-assisted web interview method was conducted in November 2022 among 2826 parents whose children attend public educational institutions in Krakow, Poland. The study group included data on 497 nursery children (17.6%), 599 kindergarten children (21.2%), 1594 primary school children (56.4%), and 136 secondary school children (4.8%).

RESULTS

Among all respondents, 72.2% were taking oral nutritional supplements, with vitamin D supplementation being particularly popular in all groups. Logistic regression analysis identified predictors of supplement use, including special diet (p < 0.001), use of medication for chronic disease (p = 0.012), regularity of main meals (p = 0.022), and attending a sports school (p = 0.021). A decrease in supplement use was observed with the increasing level of education of children (p < 0.001).

CONCLUSIONS

These results highlight the importance of various health, dietary, and sociodemographic factors in influencing decisions regarding dietary supplementation in children. Further assessment of dietary supplement usage should be conducted alongside evaluations of nutrient intake from the children's diet.

Effect of Consuming Salmon Products on Vitamin D Status of Young Caucasian Women in Autumn-A Randomized 8-Week Dietary VISA 2 (Vitamin D in Salmon Part 2) Intervention Study

BACKGROUND/OBJECTIVES

Young women are often at risk of vitamin D deficiency, while fatty fish can provide significant amounts of it, which is especially important when no vitamin D skin synthesis is possible due to limited sunshine exposure. This study aimed to analyze the impact of increasing the intake of salmon in various forms (smoked salmon, salmon sausages) on vitamin D status of young women in autumn.

METHODS

The 8-week intervention involved 120 non-obese women, aged 20-25 years. Participants were randomly assigned to one of three groups: smoked salmon (25 g/day), salmon sausage (100 g/day), or a control group. Both intervention products provided approximately 5 µg of vitamin D daily. Serum concentrations of 25(OH)D as well as vitamin D intakes were assessed pre-, mid-, and post-intervention.

RESULTS

The median vitamin D intake at baseline was 2.7-3.4 µg/day and did not differ between the groups (p > 0.05), while during the intervention, it was highest in the smoked salmon group (p < 0.001) and amounted to 7.3 µg/day. While all groups experienced a decrease in 25(OH)D serum concentrations, the decrease was significantly smaller in the salmon sausage group compared to the control group (-4.3 vs. -15.0 nmol/L, p < 0.05), and no significant difference was observed between the smoked salmon and control group after 8 weeks (p > 0.05). Moreover, in the salmon sausage group, the intervention was more effective among participants with an inadequate vitamin D status at baseline (25(OH)D change after the intervention: -3.0 vs. -5.4 nmol/L, p < 0.05; inadequate vs. adequate baseline vitamin D status).

CONCLUSIONS

Increasing the intake of salmon, and hence of vitamin D, was not enough to maintain the vitamin D status of young women in autumn. It seems that other, not-yet-fully-understood factors, may influence vitamin D absorption and/or metabolism, thereby affecting the outcomes of such interventions indicating that further research is needed. Nevertheless, it may be concluded that increasing salmon sausage intake might aid slow down the natural decline of 25(OH)D in young women in autumn.

Vitamin D Supply of Twins during Fetal Life, Its Relation to Anthropometric Parameters of Newborns and the Analysis of Other Factors Related to Birth Size

BACKGROUND/OBJECTIVES

Vitamin D deficiencies are very common in pregnant women, raising concerns about adverse health outcomes in children. This issue has hardly been studied in multiple pregnancies, the prevalence of which has been steadily increasing. Therefore, our study investigated the relationship between newborns' anthropometric parameters and the concentration of 25(OH)D in maternal blood of women with twin pregnancies and umbilical cord blood.

METHODS

The study included 50 women who gave birth after the 36th week of twin gestation. The concentration of 25(OH)D was determined in maternal blood collected during the antenatal period and in the umbilical cord blood of 100 newborns. Anthropometric parameters of the newborns (birth weight, length and head and chest circumference) were obtained from hospital records. Data on nutrition and lifestyle during pregnancy were collected from the patients during an interview conducted by a dietitian.

RESULTS

No relationship between maternal and neonatal cord blood vitamin D concentrations and any of the anthropometric parameters of the newborns was found. However, only 6% of the mothers and 13% of the newborns had vitamin D deficiency (≤20 ng/mL). The type of pregnancy and maternal height were the main factors associated with neonatal size. Newborns from dichorionic pregnancies were on average 202 g heavier (p < 0.001) and 1 cm longer (p = 0.006) than newborns from monochorionic pregnancies. Newborns of mothers ≤160 cm in height had on average 206 g lower birth weight (p = 0.006) and were 3.5 cm shorter (p = 0.003) compared to newborns of taller mothers.

CONCLUSIONS

Therefore, in our study, the neonatal size of twins was not related to the vitamin D status but to other factors such as the type of pregnancy and maternal height.

Potentially Inappropriate Prescribing Identified Using STOPP/START Version 3 in Geriatric Patients and Comparison with Version 2: A Cross-Sectional Study

Background: Multimorbidity, polypharmacy, and inappropriate prescribing are significant challenges in the geriatric population. Tools such as the Beers List, FORTA, and STOPP/START criteria have been developed to identify potentially inappropriate prescribing (PIP). STOPP/START criteria detect both potentially inappropriate medications (PIMs) and potential prescribing omissions (PPOs). The latest, third version of STOPP/START criteria expands the tool, based on the growing literature. The study aimed to evaluate the prevalence of PIP and the number of PIP per person identified by STOPP/START version 3 and to compare it to the previous version. Methods: This retrospective, cross-sectional study enrolled one hundred geriatric patients with polypharmacy from two day-care centers for partially dependent people in Poland. Collected data included demographic and medical data. STOPP/START version 3 was used to identify potentially inappropriate prescribing, whereas the previous version served as a reference. Results: STOPP version 3 detected at least one PIM in 73% of the study group, a significantly higher result than that for version 2 (56%). STOPP version 3 identified more PIMs per person than the previous version. Similarly, START version 3 had a significantly higher prevalence of PPOs (74% vs. 57%) and a higher number of PPOs per person than the previous version. The newly formed STOPP criteria with high prevalence were those regarding NSAIDs, including aspirin in cardiovascular indications. Frequent PPOs regarding newly formed START criteria were the lack of osmotic laxatives for chronic constipation, the lack of mineralocorticoid receptor antagonists, and SGLT-2 inhibitors in heart failure. Conclusions: This study showed the high effectiveness of the STOPP/START version 3 criteria in identifying potentially inappropriate prescribing, with a higher detection rate than version 2.

Anticancer Activity of Vitamin D, Lumisterol and Selected Derivatives against Human Malignant Melanoma Cell Lines

Despite the recent development of improved methods of treating melanoma such as targeted therapy, immunotherapy or combined treatment, the number of new cases worldwide is increasing. It is well known that active metabolites of vitamin D3 and lumisterol (L3) exert photoprotective and antiproliferative effects on the skin, while UV radiation is a major environmental risk factor for melanoma. Thus, many natural metabolites and synthetic analogs of steroidal and secosteroidal molecules have been tested on various cancer cells and in animal models. In this study, we tested the anti-melanoma properties of several natural derivatives of vitamin D3 and L3 in comparison to 1,25-dihydroxyvitamin D3 (1,25(OH)2D3). A significant decrease in melanoma cell proliferation and cell mobility was observed for selected derivatives, with (25R)-27-hydroxyL3 showing the highest potency (lowest IC50) in A375 cells but lower potency in SK-MEL-28 cells, whereas the parent L3 failed to inhibit proliferation. The efficacy (% inhibition) by 1,24,25(OH)3D3 and 1,25(OH)2D3 were similar in both cell types. 1,25(OH)2D3 showed higher potency than 1,24,25(OH)3D3 in SK-MEL-28 cells, but lower potency in A375 cells for the inhibition of proliferation. As for 1,25(OH)2D3, but not the other derivatives tested, treatment of melanoma cells with 1,24,25(OH)3D3 markedly increased the expression of CYP24A1, enhanced translocation of the vitamin D receptor (VDR) from the cytoplasm to the nucleus and also decreased the expression of the proliferation marker Ki67. The effects of the other compounds tested were weaker and occurred only under certain conditions. Our data indicate that 1,24,25(OH)3D3, which has undergone the first step in 1,25(OH)2D3 inactivation by being hydroxylated at C24, still shows anti-melanoma properties, displaying higher potency than 1,25(OH)2D3 in SK-MEL-28 cells. Furthermore, hydroxylation increases the potency of some of the lumisterol hydroxy-derivatives, as in contrast to L3, (25R)-27(OH)L3 effectively inhibits proliferation and migration of the human malignant melanoma cell line A375.

Assessment of the quality and content of clinical practice guidelines for vitamin D and for immigrants using the AGREE II instrument: global systematic review

BACKGROUND

Worldwide, more immigrants experience vitamin D (vitD) deficiency than non-immigrants. Recommendations in current clinical practice guidelines (CPGs) concerning vitD are inadequate to address vitD deficiency among immigrants, and there are concerns regarding the quality of guidance in these CPGs.

OBJECTIVES

This study aimed to identify and evaluate the quality of published CPGs addressing vitD and immigrants' health using the Appraisal of Guidelines for Research and Evaluation-II (AGREE II) tool and clarify the recommendations pertaining to vitD and immigrant populations in these CPGs.

METHODS

We performed a systematic search to identify the most recent CPGs across various databases (Ovid MEDLINE ALL, Embase and Turning Research Into Practice), guideline repositories and grey literature. Two reviewers independently conducted study selection and data abstraction and evaluated the quality of the included guidelines using the AGREE II tool.

RESULTS

We identified 25 relevant CPGs; 21 focused on vitD and 4 covered immigrants' health. Around one-quarter of the included CPGs were high quality (≥60% in at least four of the six domains, including 'rigour of development'). The highest mean scores among the six AGREE II domains were for 'clarity of presentation' and 'scope and purpose'. About 4.8% (1/21) of the CPGs on vitD had immigrant-related recommendations. VitD recommendations were emphasised in one out of the four immigrant health CPGs (25%). CPGs covering immigrants' health and vitD were inadequately systematically appraised. Moreover, recommendations regarding vitD were insufficient to address the growing epidemic of vitD deficiency among immigrant populations.

CONCLUSION

The insufficient recommendations for vitD fail to address the rising vitD deficiency among immigrants, highlighting a critical gap in healthcare provisions. Urgent national and international efforts are needed to develop comprehensive CPGs, bridging research, policy and practice disparities. Future guidelines must prioritise routine vitD screening, supplementation protocols for vulnerable immigrant groups, and culturally appropriate interventions to improve health outcomes for immigrants globally.

PROSPERO REGISTRATION NUMBER

CRD42021240562.

Vitamin D concentration in the blood of women with twin pregnancies and in the umbilical cord blood of newborns in relation to environmental factors

Background

There is a huge gap in the knowledge of the body's nutrient resources in women with multiple gestations. Due to the increased demand hypothesis and taking into account common vitamin D deficits in women with singleton pregnancies, this issue should also be investigated in twin pregnancies. This study evaluated blood vitamin D concentration in women with twin pregnancies and in the umbilical cord blood of their newborns as well as analyzed environmental factors that may affect the level of this nutrient.

Methods

The study included 56 women with twin pregnancies. Venous blood samples were collected from the women before delivery and umbilical cord blood at delivery to determine the total 25(OH)D concentration. The women were interviewed by a dietitian to collect data on their diet and lifestyle.

Results

The average maternal 25(OH)D concentrations were 38.4 ± 11.0 ng/mL vs. 23.7 ± 6.1 ng/mL determined in the umbilical cord blood of the newborns. The concentration of 25(OH)D in the umbilical cord blood was strongly correlated with the concentration in the mother (p < 0.001). Vitamin D deficiency was found in 7% of women and 21% of newborns. Factors increasing the risk of too low 25(OH)D concentration in the mothers were age below 27 years (p = 0.002) and short duration of pregnancy (p = 0.011). In newborns, the risk factors included low maternal concentrations (p < 0.001) and delivery before 36 weeks of gestation (p = 0.008). The mean cord blood 25(OH)D levels were almost identical in both twins and amounted to 24.0 ± 6.1 ng/mL in the first-born and 23.4 ± 6.1 ng/mL in the second-born infant. Vitamin D supplementation was declared by 98% of the women, with 85% taking ≤2,000 IU vitamin D daily.

Conclusion

Only a small percentage of women with twin pregnancies presented with vitamin D deficiency, which was probably related to the widespread supplementation of this nutrient. It can therefore be assumed that a dose of 2,000 IU vitamin D currently recommended for pregnant women may also be appropriate for twin gestations, although further research is required to validate this finding.

Seasonal variation of total and bioavailable 25-hydroxyvitamin D [25(OH)D] in the healthy adult Slovenian population

Objective: The aim of our study was to compare the total 25(OH)D fraction, the bioavailable vitamin fraction, and the free vitamin D fraction in spring and fall in a group of healthy individuals. Methods: In our study, we collected blood samples from healthy participants at the end of both summer and winter, and measured serum levels of albumin, DBP, and 25(OH)D. Utilizing these data, we calculated the percentage of free and bioavailable vitamin D. Our cohort comprised 87 participants, with a male-to-female ratio of 14:73, aged 35.95 ± 12.55 years, ranging from 19 to 70 years. We employed the chemiluminescence method to determine the vitamin 25(OH)D levels, the ELISA method was utilized to determine DBP levels, the albumin BCP Assay was performed using the ADVIA biochemical analyzer (Siemens) and an online calculator was used to determine the free and bioavailable 25(OH)D levels. Results: Our findings indicate significantly lower 25(OH)D levels in winter (44.13 ± 17.82 nmol/L) compared to summer (74.97 ± 22.75 nmol/L; p < 0.001). For vitamin D binding protein there was no significant difference from summer (236.2 ± 164.39 mg/L) to winter (239.86 ± 141.9 mg/L; p = 0.77), albumin levels were significantly higher in summer (49.37 ± 4.15 g/L vs. 47.97 ± 3.91 g/L, p = 0.01), but the magnitude of the change may not be large enough to be solely responsible for the stability of vitamin D levels throughout the year. In the winter season a significantly lower calculated bioavailable 25(OH)D vitamin (7.45 ± 5.66 nmol/L against 13.11 ± 8.27 nmol/L; p < 0.001) was observed, and the free fraction also showed a significant decrease (17.3 ± 12.9 pmol/L versus 29.7 ± 19.1 pmol/L; p < 0.0001). We observed a moderately positive correlation between 25(OH)D and bioavailable percentage in winter (r = 0.680; p < 0.001), in contrast with a lower positive association in summer (r = 0.343; p < 0.001). Conclusion: Our data suggest a positive correlation between total and bioavailable 25(OH)D levels. In addition to the statistically significant variation in 25(OH)D between the two observation periods, there was an additional variation in the free vitamin D percentage. The summertime synthesis of vitamin D in the skin could contribute directly to the free fraction of vitamin D. Standardizing the measurement of free 25(OH)D and clinical studies is necessary to establish reference values before these methods can be implemented in clinical practice.

Osteoporosis and Bone Fragility in Children: Diagnostic and Treatment Strategies

The incidence of osteoporosis in children is increasing because of the increased survival rate of children with chronic diseases and the increased use of bone-damaging drugs. As childhood bone fragility has several etiologies, its management requires a thorough evaluation of all potentially contributing pathogenetic mechanisms. This review focuses on the main causes of primary and secondary osteoporosis and on the benefits and limits of the different radiological methods currently used in clinical practice for the study of bone quality. The therapeutic and preventive strategies currently available and the most novel diagnostic and treatment strategies are also presented. Optimal management of underlying systemic conditions is key for the treatment of bone fragility in childhood. DXA still represents the gold standard for the radiologic evaluation of bone health in children, although other imaging techniques such as computed tomography and ultrasound evaluations, as well as REMS, are increasingly studied and used. Bisphosphonate therapy is the gold standard for pharmacological treatment in both primary and secondary pediatric osteoporosis. Evidence and experience are building up relative to the use of monoclonal antibodies such as denosumab in cases of poor response to bisphosphonates in specific conditions such as osteogenesis imperfecta, juvenile Paget's disease and in some cases of secondary osteoporosis. Lifestyle interventions including adequate nutrition with adequate calcium and vitamin D intake, as well as physical activity, are recommended for prevention.

Daily and Weekly "High Doses" of Cholecalciferol for the Prevention and Treatment of Vitamin D Deficiency for Obese or Multi-Morbidity and Multi-Treatment Patients Requiring Multi-Drugs-A Narrative Review

Daily vitamin D supplementation using higher than normal dosing (up to the upper limit value) and intermittent (once or twice per week) dosing were studied in patients with increased risk of vitamin D deficiency. Using a PubMed database, a thorough search for published randomized controlled trials and other studies was conducted, and the results were analyzed. This review provides an overview of the use of 7000 IU daily, 30,000 IU per week or twice weekly, and 50,000 IU weekly of vitamin D for obtaining and maintaining 25(OH)D concentrations of at least 30 ng/mL in patients at high risk of vitamin D deficiency. The abovementioned dosages should be considered in adults with obesity, liver disease or malabsorption syndromes, or multi-diseased patients, mainly seniors requiring multi-drug treatment, including drugs affecting vitamin D metabolism. The simple schedules of 7000 IU/day, 30,000 IU/week or twice weekly, and 50,000 IU/week for use by patients with an increased risk of vitamin D deficiency were provided for consideration. Without monitoring of 25(OH)D, daily doses of 7000 IU or intermittent doses of 30,000 IU/week should be considered for a prolonged time as prophylactic or maintenance doses, mainly in obese patients, patients with liver disease and patients with malabsorption syndromes. For the treatment of possible vitamin D deficiency without assessment of 25(OH)D in these groups, intermittent doses of 30,000 IU twice weekly or 50,000 IU per week should be considered for a 6-8-week period only. The higher daily doses or the intermittent doses suggested above are effective, safe and responsive based on patient's preferences.

Association of serum 25-hydroxy vitamin D status with cardiometabolic risk factors and total and regional obesity in southern Iran: evidence from the PoCOsteo study

Cardiometabolic risk factors increase the chance of developing cardiovascular disease (CVD) and type 2 diabetes. Most CVD risk factors are influenced by total and regional obesity. A higher risk of developing CVD may be linked to vitamin D deficiency, which is more prevalent in the older population. With the goal of evaluating the association between vitamin D and cardiometabolic risk factors and total and regional obesity in older adults, this research included 25 (OH) vitamin D3 concentrations and biochemical markers associated with cardiometabolic diseases, as well as total and regional adiposity, which was measured by DXA. A total of 1991 older participants in the PoCOsteo study were included. Overall, 38.5% of participants had vitamin D deficiency. After adjusting for confounders, the results of multiple linear and logistic regression suggested an inverse association between vitamin D and body mass index (P = 0.04), waist circumference (P = 0.001), total fat (P = 0.02), android fat (P = 0.001), visceral fat (P < 0.001), subcutaneous fat (P = 0.01), trunk fat (P = 0.006), arm fat (P = 0.03), high systolic blood pressure (P = 0.004), high total cholesterol (P < 0.001), high LDL-cholesterol (P < 0.001), high serum triglycerides (P = 0.001), and high fasting glucose (P < 0.001). Additionally, higher vitamin D concentrations decreased the risk of dyslipidemia by 2%. Our results showed a significant association between serum vitamin D and a number of cardiometabolic risk factors, including total and regional obesity.

Cord blood vitamin A and vitamin D levels in relation to physical growth in exclusively breastfed infants aged 0-6 months

Background

Vitamins A and D are essential for the health of pregnant women and infants. Nevertheless, the relationship between umbilical cord blood vitamins A and D levels and the physical growth of exclusively breastfed infants remains uncertain.

Objective

This cohort study aims to examine the relationship between cord blood vitamins A and D levels and the physical growth of exclusively breastfed infants aged 0-6 months.

Methods

140 singleton mother-infant pairs were recruited in total. Questionnaires were used to collect maternal and infant information, and liquid chromatography was utilized to quantify the levels of vitamins A and D in the umbilical cord blood. Anthropometric measurements were conducted at birth, at 3 and 6 months of age, and the weight-for-age z-score (WAZ), length-for-age z-score (LAZ), head circumference-for-age z-score (HAZ), and BMI-for-age z-score (BMIZ) were calculated. Univariate and multivariate linear regression models were used for the analysis.

Results

The average concentration of vitamins A and D in cord blood was 0.58 ± 0.20 μmol/L and 34.07 ± 13.35 nmol/L, both below the normal range for children. After adjusting for confounding factors, vitamin A levels in cord blood positively correlated with HAZ growth in infants aged 3-6 months (β= 0.75, P < 0.01) while vitamin D levels negatively correlated with LAZ growth (β= -0.01, P = 0.01) and positively correlated with BMIZ growth (β= 0.02, P < 0.01).

Conclusion

Higher Vitamin A levels at birth promote HAZ growth in infants aged 3-6 months while higher vitamin D levels at birth promote BMIZ growth in infants aged 3-6 months.

Clinical trial registration

https://register.clinicaltrials.gov, identifier NCT04017286.

Chronic Atrophic Autoimmune Gastritis: The Evolving Role of Vitamin D

Vitamin D possesses a crucial role in preserving bone health, modulating the immune system responses, and supporting various physiological functions throughout the body. Chronic atrophic autoimmune gastritis (CAAG) constitutes an autoimmune condition marked by inflammation and damage to the stomach cells, often resulting in a decreased ability to absorb certain nutrients, including vitamin B12 and iron. Although, vitamin D is not directly affected by this condition, the sufficiency of this micronutrient seems to have important implications for overall health and management of the disease. The aim of the current review was to assess the incidence and related features of vitamin D deficiency in patients with CAAG and to elucidate the complex regulatory role of this nutrient, in an effort to improve patient outcomes. Vitamin D greatly contributes to the regulation of the immune system. In patients with CAAG, the immune system attacks the stomach lining; thus, the maintenance of a healthy and balanced immune response is important. In autoimmune conditions such as CAAG, where inflammation plays a decisive role in disease progression, vitamin D could potentially exert a role in managing and controlling the associated symptoms. Adequate vitamin D levels may help in regulating the immune response and reducing inflammation. In addition, patients with CAAG are at risk of nutrient deficiencies, including vitamin B12 and iron, which can lead to anemia and bone health issues. As vitamin D is critical for calcium absorption and bone health, assurance of sufficient levels of this micronutrient can be beneficial in preventing or mitigating bone-related complications. In conclusion, regular monitoring of vitamin D levels, among other nutrients, and appropriate supplementation, when necessary, can help improve overall health and well-being in these patients.

Vitamin D Status among 2-18-Year-Old Romanian Pediatric Patients: A Single-Center Study

An adequate vitamin D level is essential for optimal bone mass formation during growth. The present study aimed to assess (i) the sex-specific, age-specific, and potential seasonal (spring, summer, winter) influences on the pediatric circulating levels of 25-hydroxyvitamin D (25(OH)D); (ii) determine the frequency of pediatric patients with vitamin D deficiency (VDD) or insufficiency (VDI); and (iii) quantify the association between age category, sex, and season types and susceptibility to VDD and VDI, respectively. Laboratory data were collected on serum 25(OH)D levels in children aged between 2 and 18 years (n = 1674) who underwent blood sampling following admission to a university pediatric hospital in Cluj-Napoca (Romania) between January and June 2023. VDD (<20 ng/mL) was observed in 27% of pediatric patients. Among toddlers and preschoolers (2-5 years), VDD was 11%, while it was 33% among school-aged children (6-11 years) and 39% among adolescents (12-18 years). We found a significant difference in the frequencies of vitamin D status between females and males (p = 0.006). Also, we found significant associations of vitamin D status with age categories (p < 0.0001) and seasonal variations (p = 0.03). After adjusting for season of blood collection, the multinomial logistic regression model showed that children aged 6-11 years old (adjusted OR = 7, 95% CI: (4.9, 9.4)), children aged 12-18 years old (adjusted OR = 14, 95% CI: (9.3, 19.6)), and females (adjusted OR = 1.43, 95% CI: (1.10, 1.86)) were significantly associated with higher odds of VDD. In conclusion, the study revealed a significant difference in the frequency of VDD and VDI among pediatric patients older than six years, with a significant difference according to sex and season, being more pronounced among girls and during the winter and spring seasons.

The Role of Vitamin D and Vitamin D Receptor Gene Polymorphisms in the Course of Inflammatory Bowel Disease in Children

Background: The etiopathogenesis of inflammatory bowel disease (IBD) is still unclear. Prior studies suggest genetic components that may influence the incidence and severity of the disease. Additionally, it was shown that low levels of serum vitamin D may have an impact on the clinical course of the disease due to its effect on the immunological system. Methods: We aimed to investigate the correlation between the incidence of vitamin D receptor (VDR) gene polymorphisms (rs11568820, rs10735810, rs1544410, rs7975232, and rs731236, commonly described as Cdx2, FokI, Bsm, ApaI, and TaqI, respectively) and vitamin D concentration with the clinical course of IBD (disease activity, extent of the intestinal lesions). Data were obtained from 62 patients with IBD (34 with Crohn's disease, 28 with ulcerative colitis), aged 3-18 years, and compared with controls (N = 47), aged 8-18 years. Results: Although there was no difference in the incidence of individual genotypes between the study groups (IBD, C) in all the polymorphisms examined, we described a significant increase in the chance of developing IBD for heterozygotes of Cdx2 (OR: 2.3, 95% CI 0.88-6.18, p = 0.04) and BsmI (OR: 2.07, 95% CI 0.89-4.82, p = 0.048) polymorphisms. The mean serum 25OHD level in patients with IBD was significantly higher compared with the controls (19.87 ng/mL vs. 16.07 ng/mL; p = 0.03); however, it was still below optimal (>30 ng/mL). Furthermore, a significant correlation was found between vitamin D level and TaqI in patients with IBD (p = 0.025) and patients with CD (p = 0.03), as well as with the BsmI polymorphism in patients with IBD (p = 0.04) and patients with CD (p = 0.04). A significant correlation was described between the degree of disease activity and genotypes for the FokI polymorphism in patients with UC (p = 0.027) and between the category of endoscopic lesions and genotypes for the Cdx2 polymorphism also in patients with UC (p = 0.046). Conclusions: The results suggest a potential correlation of VDR gene polymorphism with the chance of developing IBD, and the clinical course of the disease requires further studies in larger group of patients. Vitamin D supplementation should be recommended in both children with inflammatory bowel disease and in healthy peers.

Structural diversification of vitamin D using microbial biotransformations

Vitamin D deficiencies are linked to multiple human diseases. Optimizing its synthesis, physicochemical properties, and delivery systems while minimizing side effects is of clinical relevance and is of great medical and industrial interest. Biotechnological techniques may render new modified forms of vitamin D that may exhibit improved absorption, stability, or targeted physiological effects. Novel modified vitamin D derivatives hold promise for developing future therapeutic approaches and addressing specific health concerns related to vitamin D deficiency or impaired metabolism, such as avoiding hypercalcemic effects. Identifying and engineering key enzymes and biosynthetic pathways involved, as well as developing efficient cultures, are therefore of outmost importance and subject of intense research. Moreover, we elaborate on the critical role that microbial bioconversions might play in the a la carte design, synthesis, and production of novel, more efficient, and safer forms of vitamin D and its analogs. In summary, the novelty of this work resides in the detailed description of the physiological, medical, biochemical, and epidemiological aspects of vitamin D supplementation and the steps towards the enhanced and simplified industrial production of this family of bioactives relying on microbial enzymes. KEY POINTS: • Liver or kidney pathologies may hamper vitamin D biosynthesis • Actinomycetes are able to carry out 1α- or 25-hydroxylation on vitamin D precursors.

Nutrition of aging people with diabetes mellitus: Focus on sarcopenia

As populations age, chronic diseases accumulate, and new health conditions emerge. One noteworthy pair that warrants further evaluation is diabetes mellitus and sarcopenia, given that the latter occurs in 28 % of the population aged over 50 who have diabetes mellitus. The management of both entails nutritional interventions, making the development of unified dietary recommendations an alluring strategy. This review aims to elucidate the current recommendations for the combined management of sarcopenia and diabetes, while featuring elements that require further research. The goal of nutritional management is to improve muscle mass and strength while regulating metabolic risk and glucose levels. To ensure muscle synthesis in the elderly, recommendations align at daily calorie intake that exceeds 30 kcal/kg, with adjustments based on comorbidities. Additionally, a protein intake of at least 1-1.2 g/kg/d is essential, emphasizing both daily and per-meal intake, and can be achieved through diet or branched-amino-acids supplements. Specific considerations for diabetes include restricted protein intake in diabetic nephropathy and exploring the potential link between branched amino acids and insulin resistance. Further recommendations that both promote metabolic health and have demonstrated at least a potential to increase muscle strength include prioritizing polyunsaturated fatty acids as a fat source and maintaining adequate levels of vitamin D. Clinicians should consult their patients on dietary optimization, but evidence is insufficient to recommend additional supplementation. Lastly, an emerging challenge of diabetes and sarcopenia is sarcopenic obesity, which requires the combination of a hypocaloric diet with increased protein intake.

Vitamin D3 supplementation in COVID-19 patients with cardiovascular disease and gut dysbiosis

BACKGROUND

The COVID-19 pandemic has highlighted the vulnerability of particular patient groups to SARS-CoV-2 infection, including those with cardiovascular diseases, hypertension, and intestinal dysbiosis. COVID-19 affects the gut, suggesting diet and vitamin D3 supplementation may affect disease progression.

AIMS

To evaluate levels of Ang II and Ang-(1-7), cytokine profile, and gut microbiota status in patients hospitalized for mild COVID-19 with a history of cardiovascular disease and treated with daily doses of vitamin D3.

METHODS

We recruited 50 adult patients. We screened 50 adult patients and accessed pathophysiology study 22, randomized to daily oral doses of 10,000IU vitamin D3 (n=11) or placebo (n=11). Plasma levels of Ang II and Ang-(1-7) were determined by radioimmunoassay, TMA and TMAO were measured by liquid chromatography and interleukins (ILs) 6, 8, 10 and TNF-α by ELISA.

RESULTS

The Ang-(1-7)/Ang II ratio, as an indirect measure of ACE2 enzymatic activity, increased in the vitamin D3 group (24±5pg/mL vs. 4.66±2pg/mL, p<0.01). Also, in the vitamin D3-treated, there was a significant decline in inflammatory ILs and an increase in protective markers, such as a substantial reduction in TMAO (5±2μmoles/dL vs. 60±10μmoles/dL, p<0.01). In addition, treated patients experienced less severity of infection, required less intensive care, had fewer days of hospitalization, and a reduced mortality rate. Additionally, improvements in markers of cardiovascular function were seen in the vitamin D3 group, including a tendency for reductions in blood pressure in hypertensive patients.

CONCLUSIONS

Vitamin D3 supplementation in patients with COVID-19 and specific conditions is associated with a more favourable prognosis, suggesting therapeutic potential in patients with comorbidities such as cardiovascular disease and gut dysbiosis.

Long-term ultraviolet B irradiation at 297 nm with light-emitting diode improves bone health via vitamin D regulation

Ultraviolet radiation is the primary determinant for vitamin D synthesis. Sunlight is inefficient and poses a risk, particularly for long-term exposure. In this study, we screened the most favorable wavelength for vitamin D synthesis among four types of narrowband light-emitting diodes (LEDs) and then irradiated osteoporosis rats with the optimal wavelength for 3-12 months. The 297 nm narrowband LED was the most efficient. Long-term radiation increased vitamin D levels in all osteoporotic rats and improved bone health. No skin damage was observed during irradiation. Our findings provide an efficient and safe method of vitamin D supplementation.

Association between Vitamin D Deficiency and Prediabetes Phenotypes: A Population-Based Study in Henan, China

The evidence remains inconsistent regarding whether vitamin D deficiency (VDD) increases the risk of prediabetes. This study aimed to examine whether there is sex-specific association between VDD and impaired fasting glucose (IFG) or impaired glucose tolerance (IGT) in Henan. The data were sourced from the survey of chronic diseases and nutrition in Henan. Multinomial logistic regression models based on complex sampling design and weight were developed to estimate the odds ratio (OR) and confidence interval (95%CI) for measuring the association between VDD and IFG/IGT. The prevalence rate of IGT in men was 20.1% in the VDD group, significantly higher than that in the non-VDD group (10.5%), but no significant difference was observed in women between the VDD and non-VDD groups; there were no significant differences in IFG prevalence between the VDD and non-VDD groups in either men or women. It was found that the association between VDD and IGT was statistically significant in men. The adjusted OR (95%CI) of VDD was 1.99 (1.24-3.19) for IGT in men and 14.84 (4.14-53.20) for IGT in men having a family history of DM. Thus, men with VDD were more likely to live with IGT than those without VDD, especially for men having a family history of diabetes.

Assessment of Vitamin Concentrations in Patients with Hashimoto's Thyroiditis and Their Relationships with Thyroid Function, Biochemical Status, and Anthropometric Parameters-A Preliminary Study

Hashimoto's thyroiditis (HT) is the leading cause of hypothyroidism, affecting mainly the female population. Many patients with HT have metabolic disorders and nutritional deficiencies. The aim of this study was to evaluate vitamin D, A, E, B2, and B6 concentrations, thyroid function, metabolic profile, and anthropometric parameters of patients with Hashimoto's thyroiditis. In 81 female patients with HT (study group), vitamin A and B2 concentrations were significantly lower than in 34 healthy women (control group). No differences were noted in vitamin D, E, and B6 concentrations between groups. Moreover, HT patients had similar anthropometric parameters, lipid profiles, and glucose and insulin concentrations compared to controls. This study showed some relationships between vitamin concentrations and anthropometric or biochemical profiles in HT patients. Among others, in the HT group, the concentration of vitamin D was positively correlated with the level of HDL and negatively correlated with BMI, total fat mass, and insulin level, which influence cardiovascular risk. The results indicate that patients with HT should be routinely tested for vitamin concentrations to prevent nutritional deficiencies. Further studies are also needed on the role of vitamins in the development and progression of HT and the presence of metabolic complications in this population.

Discordant Health Implications and Molecular Mechanisms of Vitamin D in Clinical and Preclinical Studies of Prostate Cancer: A Critical Appraisal of the Literature Data

Clinical and preclinical studies have provided conflicting data on the postulated beneficial effects of vitamin D in patients with prostate cancer. In this opinion piece, we discuss reasons for discrepancies between preclinical and clinical vitamin D studies. Different criteria have been used as evidence for the key roles of vitamin D. Clinical studies report integrative cancer outcome criteria such as incidence and mortality in relation to vitamin D status over time. In contrast, preclinical vitamin D studies report molecular and cellular changes resulting from treatment with the biologically active vitamin D metabolite, 1,25-dihydroxyvitamin D3 (calcitriol) in tissues. However, these reported changes in preclinical in vitro studies are often the result of treatment with biologically irrelevant high calcitriol concentrations. In typical experiments, the used calcitriol concentrations exceed the calcitriol concentrations in normal and malignant prostate tissue by 100 to 1000 times. This raises reasonable concerns regarding the postulated biological effects and mechanisms of these preclinical vitamin D approaches in relation to clinical relevance. This is not restricted to prostate cancer, as detailed data regarding the tissue-specific concentrations of vitamin D metabolites are currently lacking. The application of unnaturally high concentrations of calcitriol in preclinical studies appears to be a major reason why the results of preclinical in vitro studies hardly match up with outcomes of vitamin D-related clinical studies. Regarding future studies addressing these concerns, we suggest establishing reference ranges of tissue-specific vitamin D metabolites within various cancer entities, carrying out model studies on human cancer cells and patient-derived organoids with biologically relevant calcitriol concentrations, and lastly improving the design of vitamin D clinical trials where results from preclinical studies guide the protocols and endpoints within these trials.

Cancer Incidence Rates in the US in 2016-2020 with Respect to Solar UVB Doses, Diabetes and Obesity Prevalence, Lung Cancer Incidence Rates, and Alcohol Consumption: An Ecological Study

This article reports the results of an ecological study of cancer incidence rates by state in the US for the period 2016-2020. The goals of this study were to determine the extent to which solar UVB doses reduced cancer risk compared to findings reported in 2006 for cancer mortality rates for the periods 1950-1969 and 1970-1794 as well as cancer incidence rates for the period 1998-2002 and to determine which factors were recently associated with cancer risk. The cancer data for non-Hispanic white (European American) men and women were obtained from the Centers for Disease Control and Prevention. Indices were obtained for solar UVB at the surface for July 1992, and alcohol consumption, diabetes, and obesity prevalence near the 2016-2020 period. Lung cancer incidence rates were also used in the analyses as a surrogate for smoking, diet, and air pollution. The cancers for which solar UVB is significantly associated with reduced incidence are bladder, brain (males), breast, corpus uteri, esophageal, gastric, non-Hodgkin's lymphoma, pancreatic, and renal cancer. Lung cancer was significantly associated with colorectal, laryngeal, and renal cancer. Diabetes was also significantly associated with breast, liver, and lung cancer. Obesity prevalence was significantly associated with breast, colorectal, and renal cancer. Alcohol consumption was associated with bladder and esophageal cancer. Thus, diet has become a very important driver of cancer incidence rates. The role of solar UVB in reducing the risk of cancer has been reduced due to people spending less time outdoors, wearing sunscreen that blocks UVB but not UVA radiation, and population increases in terms of overweight and obese individuals, which are associated with lower 25-hydroxyvitamin D concentrations and the generation of systemic inflammation, which is a risk factor for cancer. A dietary approach that would reduce the risk of diabetes, obesity, lung cancer, and, therefore, cancer, would be one based mostly on whole plants and restrictions on red and processed meats and ultraprocessed foods. Solar UVB exposure for a few minutes before applying sunscreen and taking vitamin D supplements would also help reduce the risk of cancer.

The Relationship between Frontal QRS-T Angle and Vitamin D Deficiency

Background and Objectives: A deficiency in serum 25-hydroxyvitamin D levels is associated with a number of cardiovascular situations, such as high blood pressure, heart failure, atherosclerotic heart disease, and peripheral artery disease. The frontal QRS-T angle has recently been proposed as a marker of ventricular repolarization. A wider frontal QRS-T angle has been positively correlated with adverse cardiac events. The objective of our study was to examine the association between serum 25-hydroxyvitamin D level and the frontal QRS-T angle. Materials and Methods: A total of 173 consecutive patients aged 18-60 years undergoing routine cardiology check-up evaluation, and not receiving concurrent vitamin D treatment were included in the study. Patients were classified in three groups, depending on their vitamin D levels, and categorized as follows: Group 1-deficient (<20 ng/mL), Group 2-insufficient (20-29 ng/mL), or Group 3-optimal (≥30 ng/mL). The frontal QRS-T angle was determined using the automated reports generated by the electrocardiography machine. Results: The average age of participants was 45.8 (±12.2) years, and 55.5% of participants were female (p < 0.001). Individuals with low vitamin D concentrations exhibited a wider frontal QRS-T angle. It was determined that vitamin D level is an independent predictive factor for the frontal QRS-T angle. Conclusions: As the levels of 25-hydroxyvitamin D decrease, repolarization time assessed by frontal QRS-T angle is widened. Our findings indicate that lower concentrations of vitamin D may increase the susceptibility to ventricular arrhythmia.

Insight into vitamin D3 action within the ovary-Basic and clinical aspects

Vitamin D3 is a fat-soluble secosteroid predominantly synthesized in the skin or delivered with a diet. Nevertheless, recently it is considered more as a hormone than a vitamin due to its pleiotropic function within the organism ensured by widely distributed vitamin D receptors and metabolic enzymes. Besides the main role in calcium and phosphorus homeostasis, vitamin D3 was shown to regulate many cellular and metabolic processes in normal and cancerous tissues within the immune system, the cardiovascular system, the respiratory system and the endocrine system. The ovary is an important extraskeletal tissue of vitamin D3 action and local metabolism, indicating its role in the regulation of ovarian functions upon physiological and pathological conditions. This chapter reviews firstly the updated information about vitamin D3 metabolism and triggered intracellular pathways. Furthermore, the basic information about ovarian physiology and several aspects of vitamin D3 effects within the ovary are presented. Finally, the special attention is paid into possible mechanism of vitamin D3 action within ovarian pathologies such as premature ovarian failure, polycystic ovary syndrome, and ovarian cancer, considering its clinical application as alternative therapy.

Vitamin D and reproductive disorders: a comprehensive review with a focus on endometriosis

Vitamin D is a fat-soluble steroid hormone that was initially known only for regulating calcium and phosphorus levels and maintaining bone health. However, it was later discovered that many organs express vitamin D metabolizing enzymes and have a ligand for vitamin D, which regulates the expression of an extensive assortment of genes. As a result, vitamin D is indispensable for the proper function of organs, and its deficiency is believed to be a critical factor in symptoms and disorders such as cardiovascular diseases, autoimmune diseases, and cancers. The significance of vitamin D in reproductive tissues was recognized later, and studies have revealed its crucial role in male and female fertility, as well as proper reproductive function during pregnancy. Vitamin D deficiency has been identified as a risk factor for infertility, gonadal cancers, pregnancy complications, polycystic ovary syndrome, and endometriosis. However, data investigating the association between vitamin D levels and reproductive disorders, including endometriosis, have encountered inconsistencies. Therefore, the present study aims to review existing research on the effect of vitamin D on proper reproductive function, and the role of deficiency in reproductive diseases and specifically focuses on endometriosis.

Dietary intake of polish organic and conventional fruit growers and their life partners - a pilot study

Diet is one of the elements that contribute to health and quality of life. There are significant discrepancies between the diets of people living in different regions, with different beliefs, or with different approaches to sustainability and ecology. There is a lack of research on dietary intake among organic and conventional fruit growers. The aim of our study was to examine the diets of orchardists and their immediate life partners in terms of meeting energy requirements, nutrient intake and fulfillment of dietary recommendations in this group. Fifty-three participants (28 in the organic group and 25 in the conventional group) took part in the study. Dietary data were obtained using the 3-day dietary record. Body mass and height were measured and BMI was calculated. Physical activity was estimated using a questionnaire method. The study group was aged 44 ± 8 years, with a body weight of 84 ± 16 kg and a height of 172 ± 9 cm. The mean BMI was 28 ± 4 kg/m2. Mean energy intake with diet was 2170 ± 606 kcal/day with needs of 3002 (1991-5144) kcal/day. A significant proportion of the study group did not fulfill their calcium and vitamin D requirements. In addition, a significant proportion of the conventional fruit growers did not cover their needs for potassium, magnesium and vitamins: E, C, and folate. Both groups had too high an intake of cholesterol and saturated fatty acids, and too low an intake of polyunsaturated fatty acids. In conclusion, the orchardists' diets mostly provided adequate amounts of nutrients, with inadequate intakes of calcium, vitamin D, cholesterol, and fatty acids. The diets of organic fruit growers were significantly richer in selected nutrients.