Search Results (285)

The etiology of schizophrenia remains poorly understood. Although certain risk factors have been identified, effective preventive measures are still lacking. This study investigates potential preventive methods while focusing on the role of vitamin D and its status. The role of malnutrition in schizophrenia risk was first identified in studies on the Dutch Hunger Winter. Vitamin D deficiency was hypothesized as a contributing factor shortly thereafter. This review aims to explore the correlations between vitamin D deficiency at various life stages (maternal, neonatal, adult) and schizophrenia risk, as well as its effects on pharmacokinetics, neurobiology, bone health, and metabolic syndrome. The studies were retrieved from two indexed databases, PubMed and Web of Science, following PRISMA guidelines and included studies published between 2000 and 2024. No correlation was found between maternal vitamin D levels and schizophrenia in offspring while a positive correlation was observed between low neonatal vitamin D levels and schizophrenia in later life. Approximately half of the studies on adults reported mean vitamin D concentrations of below 20 ng/mL which were negatively correlated with gray matter volume and bone health while positively correlated with the prevalence of metabolic syndrome. Additionally, vitamin D levels were also found to correlate with antipsychotic drug concentrations. Full article

Background: Gestational diabetes mellitus (GDM) is a prevalent pregnancy complication globally. Maternal vitamin D deficiency has been linked to the risk of GDM. The aim of this study was to explore and synthesise current evidence on the association between vitamin D deficiency and the development of gestational diabetes in Western countries. Methods: A scoping review was conducted in accordance with the Joanna Briggs Institute (JBI) methodological framework. Relevant studies were identified through a comprehensive search across seven databases: ProQuest Public Health, Google Scholar, PubMed, ScienceDirect, The Lancet, BMC Public Health, the International Journal of Women’s Health, and Scopus. Studies were included based on predefined inclusion and exclusion criteria relevant to the research question. The review followed the JBI protocol, and the PRISMA flowchart was used to guide and visualise the study selection process. Results: Nineteen studies were included in the final analysis, comprising research predominantly from Australia (5), the United States (5), and Canada (4). The findings indicate a notable association between vitamin D deficiency and GDM risk, moderated by factors such as maternal age, ethnicity, seasonal variation, and body mass index (BMI). Older maternal age and higher BMI were linked with lower vitamin D levels and a higher incidence of GDM. Ethnic groups with darker skin tones showed higher rates of vitamin D deficiency, increasing vulnerability to GDM. Seasonal patterns revealed lower vitamin D levels during winter months, correlating with greater GDM risk. These patterns underscore the need for targeted preventive strategies, including the potential role of vitamin D supplementation. Conclusions: This review supports an observed association between maternal vitamin D deficiency and increased GDM risk, influenced by demographic and environmental factors. While the evidence points to a potential preventative role for vitamin D, further high-quality research, including systematic reviews and meta-analyses, is essential to establish causality and inform clinical guidelines. The review identifies knowledge gaps and suggests directions for future research and clinical practice. Full article

Background: Micronutrient deficiencies, particularly among pregnant women and children under five years old, remain a significant public health challenge in Nigeria. Despite existing policies and programmes, national data on prevalence and risk factors are fragmented. Objective: To synthesise the current evidence on the prevalence of key micronutrient deficiencies and associated risk factors among pregnant women and children under five years old in Nigeria. Methods: A systematic review and meta-analysis were conducted using peer-reviewed studies that were published between 2008 and 2024. The databases searched included PubMed, Scopus, and African Journals Online. After screening 1207 studies, 37 studies were included: 27 were conducted among pregnant women and 10 were among children. A meta-analysis was conducted to estimate the anaemia prevalence using a random-effects model. A narrative synthesis was conducted to synthesise evidence on other micronutrients (i.e., magnesium, copper, and vitamins C and E) due to the limited data and risk factors. Results: The pooled prevalence of anaemia was 56% among children and 54% among pregnant women. The prevalence of other micronutrient deficiencies varied widely, with a high prevalence of zinc (86.4%), magnesium (94%), and vitamin D (73.3%) deficiencies in certain regions. The identified risk factors included poor dietary diversity, lower socioeconomic status, low maternal education, infection burden, and early or high parity. Most studies were facility-based and sub-national, limiting the generalisability. Conclusions: This review highlights a high prevalence of anaemia and micronutrient deficiencies among pregnant women and children in Nigeria. Key risk factors included a poor diet, low maternal education, infections, and reproductive health challenges. Targeted, multisectoral policies are urgently needed to address these gaps and improve health outcomes. Full article

Background and Objectives: Maternal vitamin D (25-hydroxyvitamin D, 25(OH)D) deficiency during pregnancy is associated with adverse outcomes for both mother and fetus. While vitamin D supplementation is commonly recommended, dietary and lifestyle factors influencing maternal 25(OH)D levels at term remain underexplored, particularly in Southern Europe. Aim: This study aimed to investigate prenatal determinants of maternal 25(OH)D levels at the time of delivery, focusing on dietary intake, supplement use, and seasonal variation. Materials and Methods: We conducted a cross-sectional study on 248 pregnant women admitted for delivery at the General Hospital of Piraeus “Tzaneio” between September 2019 and January 2022. A structured questionnaire was used to assess prenatal intake of vitamin D-rich foods (such as fatty fish, eggs, dairy, and fortified products), supplement use (dose, frequency), sun exposure habits, and lifestyle factors. Maternal serum 25(OH)D concentrations were measured from blood samples collected at the time of admission for delivery. Statistical analysis included descriptive statistics and multivariate linear regression to identify independent dietary and supplemental predictors of maternal vitamin D status. Results: A high prevalence of maternal vitamin D deficiency (VDD) was observed, particularly during the autumn and winter months. Women who reported regular intake of vitamin D supplements (400–800 IU daily) had significantly higher 25(OH)D levels compared to those who did not. Dietary intake of vitamin D-rich foods was positively associated with maternal 25(OH)D status, although the effect size was smaller compared to supplementation. Seasonal variation, BMI, and limited sun exposure were also independent predictors. Conclusions: Both vitamin D supplementation and increased dietary intake were positively associated with maternal 25(OH)D concentrations at delivery. These findings underscore the importance of prenatal nutritional assessment and targeted supplementation strategies to prevent maternal VDD in Mediterranean populations. Full article

Background: Vitamin D is increasingly recognized not only for its role in skeletal development but also for its immunomodulatory and gastrointestinal effects. Maternal and neonatal vitamin D deficiency (VDD) has been associated with alterations in gut microbiota, impaired intestinal barrier integrity, and increased susceptibility to inflammatory conditions in neonates. However, the exact mechanisms linking perinatal vitamin D status to neonatal gastrointestinal morbidity remain incompletely understood. Methods: This review synthesizes current evidence (2015–2024) from clinical studies, animal models, and mechanistic research on the impact of VDD during pregnancy and the neonatal period on gastrointestinal health. Databases such as PubMed, Scopus, and Web of Science were systematically searched using keywords, including “vitamin D”, “neonate”, “gut microbiome”, “intestinal barrier”, and “necrotizing enterocolitis”. Results: Emerging data suggest that VDD in utero and postnatally correlates with dysbiosis, increased intestinal permeability, and elevated inflammatory responses in neonates. Notably, low 25(OH)D levels in mothers and newborns have been linked with a higher incidence of necrotizing enterocolitis (NEC), delayed gut maturation, and altered mucosal immunity. Vitamin D appears to modulate the expression of tight junction proteins, regulate antimicrobial peptides, and maintain microbial diversity through the vitamin D receptor (VDR). Conclusions: Understanding the gastrointestinal implications of early-life VDD opens a potential window for preventive strategies in neonatal care. Timely maternal supplementation and targeted neonatal interventions may mitigate gut-related morbidities and improve early-life health outcomes. Further longitudinal and interventional studies are warranted to clarify causality and optimal intervention timing. Full article

Background/Objectives: Postpartum depression (PPD) affects approximately 10–20% of women during and after pregnancy, posing significant risks to maternal health, infant development, and family dynamics. Identifying modifiable risk factors is essential for prevention. Emerging evidence suggests that vitamin D, a neuroactive steroid hormone involved in neurotransmitter synthesis, neuroinflammation regulation, and calcium homeostasis, may play a protective role against mood disorders, including PPD. Methods: The search was conducted through a comprehensive search of the PubMed, Scopus, and Web of Science databases using a combination of Medical Subject Headings (MeSH) and free-text terms including “vitamin D”, “25-hydroxyvitamin D”, “deficiency”, “pregnancy”, “postpartum”, “depression”, “antenatal depression”, “maternal mental health”, and “perinatal mood disorders”. Results: Numerous observational studies and systematic review reports around the world reinforce the potential global relevance of vitamin D insufficiency. This study advances personalized and precision medicine approaches by emphasizing the importance of individualized screening for vitamin D deficiency during pregnancy and postpartum, enabling tailored interventions that could mitigate the risk of postpartum depression. Conclusions: In conclusion, while a definitive causal relationship between vitamin D deficiency and perinatal depression remains unproven, screening for vitamin D levels during pregnancy could serve as a low-risk intervention to support maternal mental health. Future research should focus on well designed, large-scale randomized trials and standardization of diagnostic criteria to clarify vitamin D’s role in preventing perinatal depression. Recognizing vitamin D status as a modifiable biomarker allows for targeted nutritional and pharmacological strategies to optimize maternal mental health. Full article

Background/Objectives: Lactating mothers have increased nutritional requirements, but nutritional adequacy is difficult to achieve. Additionally, human milk (HM) composition depends on maternal diet. However, the nutritional intake and status of mothers with hospitalized very preterm infants (MHVPIs) (<32 weeks of gestational age) have rarely been assessed. Hence, the aim of the present study was to determine the intake of macronutrients, micronutrients, and lipids, as well as the nutritional status of MHVPIs. The results were compared with a group of HM donors (HMDs), and associations with HM composition were evaluated using multiple linear regression. Methods: For dietary assessment, a 5-day dietary record including supplement intake was completed by 15 MHVPIs and 110 HMDs. Vitamins and fatty acids (FA) were determined in plasma and erythrocytes; minerals and methylmalonic acid were determined in urine; and macronutrients, vitamins, minerals, and the lipid profile were determined in HM. Results: Considering dietary reference intakes, the dietary evaluation of MHVPIs revealed a high percentage of inadequate nutrient intake in relation to total energy, as well as for iodine and vitamins B8, B9, C, D, and E. A high protein intake was observed. The percentage of energy from carbohydrates was low, whereas the percentage of energy from fat was high. However, the diet of MHVPIs did not differ substantially from the diet of HMDs. Associations were observed between the study groups (MHVPI vs. HMD) and the HM concentration of protein, several micronutrients, and fatty acids independent from intake and status. Conclusions: Deficient nutrient intakes did not appear to be exclusively related to MHVPI but rather seemed to be widespread in both study groups. However, for preterm infants, an insufficient supply of nutrients is critical and should be addressed in order to improve preterm infant’s outcomes. Furthermore, we provided additional insights into the exploration of HM by relating its composition to prematurity. Full article

Background: Vitamin D deficiency (VDD) during pregnancy has been associated with various obstetric complications, including preeclampsia, gestational diabetes, and premature rupture of membranes. However, its potential link to placental abruption remains underexplored. The aim of this study was to investigate whether low maternal vitamin D levels are associated with an increased risk of placental abruption in pregnancies considered otherwise low-risk. Methods: We conducted a cross-sectional study involving 248 pregnant women who were admitted for delivery at a public hospital in Athens, Greece. Serum levels of 25-hydroxyvitamin D [25(OH)D] were measured upon admission. Levels below 30 ng/mL were classified as insufficient. Although this threshold corresponds to insufficiency according to the Endocrine Society, for the purposes of this study, levels < 30 ng/mL were treated as indicative of vitamin D deficiency in order to capture broader physiological implications. Cases of placental abruption were identified based on obstetric history and clinical documentation at the time of delivery. A Chi-square test was used to assess the association between vitamin D status and placental abruption, and a multivariate logistic regression model was applied to control for potential confounders, including hypertensive disorders of pregnancy, smoking, and preterm birth. The potential role of vitamin D supplementation during pregnancy was also explored as part of the analysis. Results: Our analysis revealed that women with VDD had a significantly higher incidence of placental abruption (p < 0.05). In the multivariate model, VDD remained an independent risk factor (adjusted OR: 3.2, 95% CI: 1.1–9.6). Additional risk factors that showed significant associations with placental abruption included pregnancy-induced hypertension and maternal smoking. Conclusions: These findings support the hypothesis that insufficient maternal vitamin D levels may contribute to adverse pregnancy outcomes, including placental abruption. Further prospective studies are warranted to clarify the causal mechanisms and to evaluate whether early detection and correction of vitamin D deficiency could serve as a preventive strategy in prenatal care. Full article

Background: Recently, vitamin D deficiency (VDD) has been described as a pandemic, affecting all groups of the population. Pregnant women and preterm infants are particularly vulnerable to vitamin D deficiency. Objectives: We aimed to evaluate the maternal and neonatal vitamin D status in relation with maternal vitamin D supplementations during pregnancy and to identify demographic, social, and healthcare risk factors for maternal VDD and vitamin D insufficiency in women delivering at ≤32 weeks of gestation. Methods: This prospective observational study was developed in the regional level III maternity unit of the Clinical County Emergency Hospital Sibiu. It included all admitted mothers who delivered at ≤32 weeks of gestation and their infants between 1 March 2022 and 28 February 2025. Infant deaths in the first 24 h of life, major congenital defects, chromosomal abnormalities, the admission of outborn infants without their mothers, or the transfer of the mother more than 48 h after birth were used as exclusion criteria. Maternal and neonatal data were collected from medical records. Data on maternal vitamin D supplementation were collected through interviews. Univariate and multivariate logistic regressions, linear regression, and predictive models were performed for data analysis. Results: A total of 146 mothers (median (IQR) age 30 (24–35) years) and their 164 preterm infants born at ≤32 weeks of gestation (median gestational age of 30 (27–31) weeks and birth weight of 1200 (900–1527) g) were included in this study. Only 43.15% of the mothers used multivitamins containing vitamin D during pregnancy, and 10.96% used specific vitamin D supplements. Vitamin D supplementation was used for a median of 4 (3–5) months at a median dose of 800 (250–1500) IU/day. Severe VDD (25(OH)D < 10 ng/mL), VDD (25(OH)D < 20 ng/mL), VDI (25(OH)D 20–29 ng/mL) were found in 19.86%, 55.48%, and 23.97% of the mothers and 16.46%, 58.53%, and 25.61% of their infants, respectively. A significant correlation was found between the maternal and neonatal status (r = 0.684, r² = 0.468, p < 0.001, B = 0.62). Both the maternal and neonatal vitamin D status were correlated with the vitamin D duration and dose used for supplementation during pregnancy. The logistic regression analysis showed that birth during a cold season and increased parity are independently associated with severe maternal VDD, while birth during the cold season and a lower educational status were independently associated with maternal VDD. Only an absent vitamin D supplementation (in the form of a multivitamin or specific vitamin D supplements) has been proven as an independent risk factor for VDI. Conclusions: Our findings revealed a worrisome prevalence of severe VDD, VDD, and VDI in mothers delivering very prematurely and in their infants. Additionally, less than half of the mothers in this study used vitamin D supplements during pregnancy despite the national recommendations. The professionals involved in advising pregnant women and policymakers should find solutions to improve the vitamin D status in these vulnerable groups of the population. Full article

Background: Pre-eclampsia (PE) is a common and serious pregnancy complication, contributing significantly to maternal and neonatal morbidity and mortality. Emerging evidence suggests a potential link between vitamin D deficiency (VDD) and an increased risk of PE. However, the data remain inconclusive, and the precise role of vitamin D supplementation in preventing PE is still uncertain. This systematic review and meta-analysis aims to evaluate the association between maternal VDD and the risk of pre-eclampsia, specifically focusing on randomized controlled trials (RCTs) to assess the potential preventive effect of vitamin D supplementation during pregnancy. Methods: A systematic review and meta-analysis were conducted by reviewing RCTs that investigated the link between maternal VDD and the incidence of pre-eclampsia. The studies were sourced from major databases such as PubMed, Scopus, and Web of Science, with studies published from 2016 to 2025. A random-effects model was employed to calculate pooled risk ratios (RRs) with 95% confidence intervals (CIs). Results: A total of 2461 participants were included from the five RCTs. The meta-analysis revealed a significant reduction in the risk of pre-eclampsia among pregnant women receiving vitamin D supplementation (RR = 0.61, 95% CI: [0.50–0.75], p < 0.001), supporting its protective role. Subgroup analysis revealed that the association was particularly strong in women with serum vitamin D levels < 20 ng/mL. Additionally, supplementation with vitamin D showed a trend towards reducing the risk of pre-eclampsia, although the studies showed some heterogeneity regarding supplementation dosages and timing. Conclusions: This systematic review and meta-analysis provides robust evidence that maternal VDD is associated with an increased risk of pre-eclampsia. The findings suggest that correcting VDD through supplementation during pregnancy may be an effective preventive strategy to reduce the incidence of pre-eclampsia. However, further well-designed RCTs are required to determine the optimal timing, dosage, and long-term effects of vitamin D supplementation on maternal and neonatal health outcomes. Full article

Background: This study aimed to investigate the long-term effects of maternal exposure to fine particulate matter (PM_2.5) with or without vitamin D supplementation on the renal microvasculature in adult rat offspring. Methods: Pregnant Sprague–Dawley rats were exposed to normal saline, PM_2.5, and PM_2.5 with vitamin D for one month during nephrogenesis. Male offspring kidneys were taken for analyses on postnatal day 56. Results: Adult offspring rats exposed to maternal PM_2.5 exhibited lower body weights and greater glomerular and tubular injury scores compared to control rats. Semi-quantitative analysis revealed a significant reduction in glomerular and peritubular capillary endothelial cells, along with a decrease in the number of glomeruli in the PM_2.5 group. Maternal vitamin D supplementation reduced these changes. In offspring rats exposed to maternal PM_2.5, intrarenal expression of renin, angiotensin-converting enzyme (ACE), cytochrome P450 27B1, and vascular endothelial growth factor-A (VEGF-A) increased, while expression of the vitamin D receptor, Klotho, VEGF receptor 2, angiopoietin-1, and Tie-2 decreased. Maternal vitamin D supplementation restored VEGF receptor 2 and angiopoietin-1 activities and reduced ACE and VEGF-A protein expression in adult offspring kidneys. Conclusions: Early-life exposure to PM_2.5 may lead to long-term alterations in renal microvasculature and nephron loss. Maternal vitamin D supplementation during renal development can ameliorate PM_2.5-induced capillary rarefaction and nephron loss in the kidneys of adult offspring. Full article

Background: Vitamin D is essential for neonatal health, with maternal vitamin D status crucial in fetal development and neonatal outcomes. During pregnancy, vitamin D is transferred to the fetus via the placenta, forming an initial reserve. Postnatally, neonates rely on maternal levels and supplementation due to limited sunlight exposure and immature skin synthesis. Objectives: This review evaluates neonatal vitamin D deficiency’s causes and clinical consequences, emphasizing its impact on newborn and infant health. Results: Maternal vitamin D levels strongly correlate with neonatal 25(OH)D concentrations, influencing birth weight, bone development, and overall health. Supplementation during pregnancy reduces the risk of severe deficiencies and rickets, particularly in exclusively breastfed infants who require daily supplementation of 400 IU. Formula-fed infants typically meet requirements through fortified formulas. Preterm infants are at a higher risk of complications like osteopenia and rickets, with mixed evidence on the effectiveness of higher supplementation doses. Vitamin D is critical in skeletal development, immune function, and protection against respiratory infections such as bronchiolitis and pneumonia. Deficiency is associated with respiratory distress syndrome (RDS), atopic dermatitis, and impaired bone mineralization due to reduced placental calcium transport. Conclusions: Vitamin D deficiency during pregnancy and infancy has significant clinical implications, including impaired skeletal and immune development. Maternal and neonatal supplementations are critical to prevent deficiencies, particularly in high-risk groups such as preterm and breastfed infants. Targeted strategies are essential to improve neonatal health outcomes and prevent complications. Full article

Autism Spectrum Disorder (ASD) has been associated with disruptions in one-carbon metabolism and vitamin D pathways. Nutritional exposures—particularly vitamin D, vitamin B₁₂, and homocysteine—may influence neurodevelopmental outcomes. However, a comprehensive, lifespan-spanning synthesis of these modifiable nutritional biomarkers has not been conducted. This systematic review and stratified meta-analysis critically synthesized data on vitamin D, vitamin B₁₂, and homocysteine to elucidate their relationships with ASD risk and symptomatology. Our central question was: How do levels of vitamin D, vitamin B₁₂, and homocysteine—measured before and after birth—affect the risk, severity, and potential treatment outcomes for ASD? We conducted a PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) compliant systematic review and stratified meta-analysis (2015–2025) of 35 studies (11 randomized controlled trials, 24 observational), examining prenatal, neonatal, and postnatal biomarker levels. Eligibility criteria were defined using the PICOS (Population, Intervention, Comparator, Outcome, and Study Design) framework to ensure scientific rigor and clinical relevance, including studies involving human participants aged 0–18 years with a formal Autism Spectrum Disorder (ASD) diagnosis or prenatal exposures potentially linked to later ASD onset, while excluding animal studies, adult-only ASD populations, and studies lacking ASD cohorts or biomarker data. The search strategy, developed according to PRISMA, and Cochrane best practices, encompassed five major databases (PubMed/MEDLINE, Cochrane Library, Google Scholar, ClinicalTrials.gov, and ProQuest) alongside manual searches of key references, grey literature, and clinical trial registries to ensure comprehensive retrieval of both published and unpublished studies. Study quality was assessed using version 2 of the Cochrane risk-of-bias tool for RCTs (RoB2) and the Newcastle–Ottawa Scale (NOS) for observational studies; certainty of evidence was graded via GRADE (Grading of Recommendations Assessment, Development and Evaluation). Random-effects meta-analyses were stratified by biomarker and study design. Heterogeneity, small-study effects, and publication bias were evaluated using Cochran’s Q, I², Egger’s test, and trim-and-fill. Prenatal vitamin D deficiency was associated with approximately two-fold increased odds of Autism Spectrum Disorder (ASD) in offspring (pooled OR ≈ 2.0; p < 0.05), while excessively elevated maternal B₁₂ concentrations, often co-occurring with folate excess, were similarly linked to increased ASD risk. Meta-analytic comparisons revealed significantly lower circulating vitamin D (SMD ≈ −1.0; p < 0.001) and B₁₂ levels (SMD ≈ −0.7; p < 0.001), alongside elevated homocysteine (SMD ≈ 0.7; p < 0.001), in children with ASD versus neurotypical controls. Early-life vitamin D/B₁₂ insufficiency and elevated homocysteine are important, modifiable correlates of ASD risk and severity. Adequate maternal and child nutritional status could have risk-reducing and symptom-mitigating effects, although causality remains to be confirmed. This evidence supports tailored nutritional interventions as a component of ASD risk reduction and management strategies, within the bounds of overall developmental healthcare. The article processing charges (APC) were supported by “Dunărea de Jos” University of Galati, Romania. No external funding was received for the execution of the research. The review was not prospectively registered in PROSPERO or any other systematic review registry. Full article

Background: The role of vitamin D deficiency (VDD) in both mothers and neonates has been suggested as a possible factor in the development of allergic conditions in early infancy, however limited research has investigated this link in relation to allergic rhinitis (AR). This study investigates whether VDD in the mother–newborn dyad is associated with the onset of AR in neonates within the first three days after birth. The aim is to contribute to the understanding of neonatal allergic outcomes related to vitamin D status, which may inform future preventive strategies. This study investigates the role of vitamin D in the early onset of allergic rhinitis (AR) in neonates, specifically within the first three days of life. Although AR typically develops after years of allergen exposure and is rare in children under two, we aimed to explore its occurrence at this early stage. While no clear link was found between vitamin D and early AR onset, further research is needed to explore vitamin D levels at later ages and over longer time frames to clarify the relationship. Methods: A cross-sectional study was conducted between September 2019 and January 2022 in a single hospital. The study involved 248 infants born at ≥37 weeks of gestation and their mothers, who were of Greek nationality. The study included mother–infant pairs who met the inclusion criteria. Chi-square tests were applied to analyze the association between maternal or neonatal VDD and the presence of AR in neonates within the first three days after birth. In addition, multiple regression analysis was used to control other potential factors contributing to AR. Results: The results showed an unclear relationship between VDD and the onset of AR in neonates within the first three days of life. Although several factors were analyzed, the effect of VDD on the development of AR remained unclear. Conclusions: The findings highlight the lack of clarity regarding the effect of maternal and neonatal VDD on the incidence of AR in the immediate neonatal period. Few studies to date have specifically examined the role of VDD in neonatal AR. Further research with larger sample sizes is needed to verify these associations and to guide potential interventions aimed at reducing allergic outcomes in neonates. Full article

Background/Objectives: This systematic review aims to investigate the potential association between vitamin D levels and the occurrence of developmental enamel defects (DDE) in children, including conditions like molar–incisor hypomineralization (MIH) and hypomineralized second primary molars (HSPMs). DDEs, which occur during tooth development, can result in significant aesthetic and functional issues, and their exact etiology remains unclear, with both genetic and environmental factors contributing. Among environmental factors, vitamin D deficiency has been proposed as a possible risk factor, given its role in enamel mineralization. Methods: A thorough literature search was conducted in PubMed, Scopus, and Embase. The search strategy included terms such as “vitamin D”, “vitamin D deficiency”, “developmental defects of enamel”, “enamel hypoplasia”, “molar-incisor hypomineralization”, and “hypomineralized second primary molars”. Studies were included if they were original human observational research (cohort, case–control, or cross-sectional) conducted in children under 18 years of age or involving maternal–child cohorts. Ten studies were included in the analysis, with a total of 15,891 participants. The primary data extracted from the selected studies included the following: study design, participants’ age, sample size, vitamin D status in relation to developmental defects of enamel, and statistical significance Results: The findings were mixed, with only a few studies suggesting a significant association between low vitamin D levels and the presence of DDEs. Specifically, one study found a link between insufficient maternal vitamin D levels during pregnancy and an increased number of teeth affected by MIH in children. However, the majority of the studies did not report a significant association. Conclusions: This review concludes that while there is some evidence to suggest a possible relationship between vitamin D and DDEs, more research is needed to confirm these findings and better understand the underlying mechanisms. Full article