Low vitamin D associated with high parathyroid hormone (PTH) is commonly reported in the context of HIV infection. We determined the association between total 25-hydroxyvitamin-D [25(OH)D] and PTH in adolescents living with HIV, in Zambia and Zimbabwe. Adolescents (11-19 years) perinatally-infected with HIV and established on antiretroviral therapy (ART) for ≥6 months were recruited into a cross-sectional study. Socio-demographic and clinical characteristics were recorded, anthropometry measured, and fasted serum concentrations of 1,25-dihydroxyvitamin-D (1,25(OH)2D), total 25(OH)D and intact PTH measured. The association between total 25(OH)D and PTH was examined using natural cubic spline regression modelling. 842 participants (female: 53.2%) with median age 15.5 (IQR:13.2-17.9) years were enrolled. Median ART duration was 9.8 [IQR:6.3-12.3] years and 165/841 (19.6%) had an HIV viral load >60copies/ml. Stunting (HAZ score<-2) and underweight (WAZ score<-2) were observed in 29.9% and 30.0% respectively. Three quarters (n=639) reported daily calcium intakes <150mg/day. The mean (SD) concentrations of total 25(OH)D and 1,25(OH)2D were 66.1(16.5) nmol/L and 210.6(70.4) pmol/L respectively, and median PTH level was 4.3 (IQR:3.3-5.5) pmol/L. There was an inverse non-linear relationship between total 25(OH)D and PTH, 25(OH)D levelling-off at 74.6nmol/L (95%CI: 74.5-75.2). Results were consistent in those taking tenofovir disoproxil fumarate (81.7%) and in those who were virally unsuppressed. In this population with extremely low habitual calcium intakes, the lack of association between 25(OH)D and PTH when 25(OH)D exceeded 75nmol/L, potentially suggests levels of 25(OH)D >75nmol/l may need to be achieved to improve bone health; investigation is needed in future research studies.

Colorectal cancer (CRC), the third most common cancer globally, causes over 900 000 deaths annually. Although vitamin D is observed to have potential anti-carcinogenic properties, research findings on its preventable effect against CRC remain inconclusive. Notably, different subsites within the colon and rectum may be associated with distinct risk factors. While some studies have explored this relationship with circulating 25-hydroxyvitamin D (25(OH)D), the results remain contradictory. Our study employed a nested case–control design, involving 775 CRC cases matched with 775 cancer-free controls based on age, region of living and the time of blood sampling. The study was conducted within the Norwegian Women and Cancer post-genome cohort, which comprises approximately 50 000 women. We measured pre-diagnostic circulating plasma 25(OH)D status 5–13 years before diagnosis. Adjustment variables were based on self-administered questionnaires and included BMI, physical activity level, smoking, intake of processed meat, calcium, alcohol and fibre. An increase of 5 nmol/l in 25(OH)D reduced the risk of proximal colon cancer by 6 % (OR = 0·94, 95 % CI 0·89, 0·99). Furthermore, a sensitivity analysis revealed a 62 % increased risk among the women with 25(OH)D levels below 50 nmol/l compared with sufficient levels, ≥ 50 to < 75 nmol/l (OR = 1·62, 95 % CI 1·01, 2·61). No association was found with CRC, colon or distal colon cancer. We observed a subsite-specific association between 25(OH)D and CRC, highlighting the need for further investigation to elucidate the potential underlying mechanisms and clinical implications.

The WHO describes micronutrient deficiencies, or hidden hunger, as a form of malnutrition that occurs due to low intake and/or absorption of minerals and vitamins, putting human development and health at risk. In many cases, emphasis, effort and even policy revolve around the prevention of deficiency of one particular micronutrient in isolation. This is understandable as that micronutrient may be among a group of nutrients of public health concern. Vitamin D is a good exemplar. This review will highlight how the actions taken to tackle low vitamin D status have been highly dependent on the generation of new data and/or new approaches to analysis of existing data, to help develop the evidence-base, inform advice/guidelines, and in some cases, translate into policy. Beyond focus on individual micronutrients, there has also been increasing international attention around hidden hunger, or deficiencies of a range of micronutrients, which can exist unaccompanied by obvious clinical signs but can adversely affect human development and health. A widely quoted estimate of the global prevalence of hidden hunger is a staggering two billion people, but this is now over 30 years old. This review will outline how strategic data sharing and generation is seeking to address this key knowledge gap in relation to the true prevalence of hidden hunger in Europe, a key starting point towards defining sustainable and cost-effective, food-based strategies for its prevention. The availability of data on prevalence and food-based strategies can help inform public policy to eradicate micronutrient deficiency in Europe.

Objective: This study aimed to assess and comparatively analyse two menus from a Young Offenders Institution (YOI). One menu from 2019, and one from 2022, with the objective of identifying any improvements in meeting dietary guidelines. Design: Cross-sectional and comparative analysis. Setting: United Kingdom, a YOI in Northern England. Participants: YOI Menus. Results: Analysis of 30 dietary components identified that 25 exceeded the dietary guidelines (P < 0.05) for the 2022 menu, with five failing to meet the guidelines (P < 0.05). When compared to the 2019 menu, the 2022 menu showed improvements in saturated fat, sodium, and vitamin D. Despite the improvement, vitamin D levels remained below dietary guidelines (P < 0.01). Salt and energy content were reduced in the 2022 menu (P < 0.05); however, they were still above the dietary guidelines (P < 0.01). Free sugars were significantly above dietary guidelines for both menus, with no significant change between the 2019 and 2022 menu (P = 0.12). Conclusion: The 2022 menu has demonstrated progress in alignment with meeting dietary guidelines, particularly in reducing calories, fat, saturated fat, salt, sodium, and chloride, as well as increasing vitamin D. Despite improvements, calories, free sugars, salt, saturated fat, sodium, and chloride are still exceeding dietary guidelines, posing as potential health risks.

Previous studies have indicated an association between vitamin D and thyroid- and parathyroid-related diseases. However, it remains unclear whether it is a cause of the disease, a side effect of treatment or a consequence of the disease. The Mendelian randomisation (MR) study strengthens the causal inference by controlling for non-heritable environmental confounders and reverse causation. In this study, a two-sample bidirectional MR analysis was conducted to investigate the causal relationship between serum vitamin D levels and thyroid- and parathyroid-related diseases. Inverse variance weighted, weighted median and MR-Egger methods were performed, the Cochran Q test was used to evaluate the heterogeneity and the MR-PRESSO and MR-Egger intercepts were utilised to assess the possibility of pleiotropy. The Bonferroni-corrected significance threshold was 0·0038. At the Bonferroni-corrected significance level, we found that vitamin D levels suggestively decreased the risk of benign parathyroid adenoma (OR = 0·244; 95 % CI 0·074, 0·802; P = 0·0202) in the MR analyses. In the reverse MR study, a genetically predicted risk of thyroid cancer suggestively increased the risk of elevated vitamin D (OR = 1·007; 95 % CI 1·010, 1·013; P = 0·0284), chronic thyroiditis significantly increased the risk of elevated vitamin D (OR = 1·007; 95 % CI 1·002, 1·011; P = 0·0030) and thyroid nodules was significantly decreased the vitamin D levels (OR = 0·991; 95 % CI 0·985, 0·997; P = 0·0034). The findings might be less susceptible to horizontal pleiotropy and heterogeneity (P > 0·05). This study from a gene perspective indicated that chronic thyroiditis and thyroid nodules may impact vitamin D levels, but the underlying mechanisms require further investigation.

Vitamin D and cholesterol share the same intestinal transporters. Thus, it was hypothesized that dietary cholesterol adversely affects vitamin D uptake. The current studies investigated the influence of cholesterol on the availability of oral vitamin D. First, 42 wild-type mice received a diet with 25 µg/kg labelled vitamin D3 (vitamin D3-d3), supplemented with either 0% (control), 0.2%, 0.4%, 0.6%, 0.8%, 1.0% or 2.0% cholesterol for four weeks to investigate vitamin D uptake. In a second study, 10 wild-type mice received diets containing 0% (control) or 1% cholesterol over four weeks to determine cholesterol-induced changes in bile acids. Finally, we investigated the impact of cholesterol versus bile acids on vitamin D uptake in Caco-2 cells. Surprisingly, dietary cholesterol intake was associated with 40% higher serum levels of vitamin D3-d3 and 2.3-fold higher vitamin D3-d3 concentrations in the liver compared to controls. The second study showed that cholesterol intake resulted in higher concentrations of faecal bile acids (control: 3.55 ± 1.71 mg/g dry matter; 1% dietary cholesterol: 8.95 ± 3.69 mg/g dry matter; P < 0.05) and changes in the bile acid profile with lower contents of muricholic acids (P < 0.1) and higher contents of taurodeoxycholic acid (P < 0.01) compared to controls. In-vitro analyses revealed that taurocholic acid (P < 0.001) but not cholesterol increased the cellular uptake of vitamin D by Caco-2 cells. To conclude, dietary cholesterol seems to improve the bioavailability of oral vitamin D by stimulating the release of bile acids and increasing the hydrophobicity of bile.

This study aimed to determine if maternal fatty acids (FA) levels during pregnancy are associated with the occurrence of neural tube defects (NTDs) and to explore the correlation between FA and maternal vitamin D, homocysteine, vitamin B12, and folate in cases. Plasma FA composition was assessed using capillary gas chromatography. Comparisons between cases and controls were performed by independent samples t-test for continuous variables. Cases had significantly higher levels of heptadecanoic acid, linolelaidic acid, and arachidonic acid (ARA):(eicosapentaenoic acid+docosahexaenoic acid) ratio than controls (p < 0.05). Nervonic acid, ARA, adrenic acid, eicosapentaenoic acid, docosahexaenoic acid, and omega-3 polyunsaturated fatty acids (n-3 PUFA) levels were significantly lower in cases (p < 0.05). Maternal 25-hydroxyvitamin D (25(OH)D) levels were positively correlated with maternal polyunsaturated fatty acids and omega-6 polyunsaturated fatty acids. RBC folate levels were negatively correlated with n-3 PUFA.

Further research is required to clarify the association of FA metabolism with NTDs.

The aim of this study is to investigate whether 25-hydroxyvitamin D (25(OH)D) is associated with periodontitis and tooth loss in older adults. A total of 2346 adults underwent a detailed dental examination as part of the health assessment of a national population study – The Irish Longitudinal Study of Ageing. 25(OH)D analysis was performed on frozen non-fasting total plasma using LC-MS. The analysis included both multiple logistic regression and multinominal logistic regression to investigate associations between 25(OH)D concentration, periodontitis and tooth loss, adjusting for a range of potential confounders. Results of the analysis found the mean age of participants was 65·3 years (sd 8·2) and 55·3 % of the group were female. Based on the quintile of 25(OH)D concentration, participants in the lowest v. highest quintile had an OR of 1·57 (95 % CI 1·16, 2·13; P < 0·01) of having periodontitis in the fully adjusted model. For tooth loss, participants in the lowest v. highest quintile of 25(OH)D had a RRR of 1·55 (95 % CI 1·12, 2·13; P < 0·01) to have 1–19 teeth and a RRR of 1·96 (95 % CI 1·20, 3·21; P < 0·01) to be edentulous, relative to those with ≥ 20 teeth in the fully adjusted models. These findings demonstrate that in this cross-sectional study of older men and women from Ireland, 25(OH)D concentration was associated with both periodontitis and tooth loss, independent of other risk factors.

Vitamin D deficiency has previously been linked to higher rates of exacerbation and reduced lung function in asthmatics. Previous randomised controlled trials investigating the effect of vitamin D supplementation have mainly focused on children with asthma. Trials involving adults have typically used bolus dosing regimens, and the main outcomes have been patient-focused without investigating underlying inflammation. The present study aimed to conduct a 12-week placebo-controlled randomised controlled trials administering a daily 125 µg vitamin D3 supplement to adults with mild to moderate asthma. A total of 32 participants were randomised to receive either the 125 μg vitamin D3 supplement or an identical matching placebo. The primary outcome of the study was lung function measured by the ratio of FEV1:FVC (effect size 2·5) with secondary outcomes including asthma symptoms and inflammatory biomarkers. There was a small but statistically significant higher increase in the mean (±sd) ratio of FEV1:FVC from baseline to post-intervention in the vitamin D group (+0·05 ± 0·06) compared with the placebo group (+0·006 ± 0·04, P = 0·04). There was no effect of the intervention on asthma control test scores, or the inflammatory biomarkers measured. There was a moderate, significant association between baseline plasma 25(OH)D concentration and baseline plasma IL-10 (r = 0·527, P = 0·005) and TNF-α (r = −0·498. P = 0·008) concentrations. A daily vitamin D3 supplement led to slightly improved lung function in adult asthmatics and may be a useful adjunct to existing asthma control strategies, particularly for individuals with suboptimal vitamin D status.

Vitamin D deficiency and insufficiency have been found in general population but especially in women of childbearing age. Although Vitamin D can be obtained from food source (few naturally) and produced from skin sunlight exposure, it can come from a reliable source via supplementation. Supplementing 15 µg daily could meet the recommended dietary allowance for 19 years and older and 20 µg for 70 years older. Daily supplementation greater than 100 µg is not recommended. Unlike water-soluble vitamins B and C, Vitamins A, D, E, and K are fat-soluble. This property of Vitamin D affects not only the delivery of it in drink but also absorption at the small intestine and bioavailability (i.e., serum level). This study focused on enhancing the solubility of vitamin D using a novel botanical solubilizer. Using rubusoside (RUB), isolated from stevia and other plants, Vitamin D3 (cholecalciferol; VD3) was experimented for solubility enhancement. VD3 was processed with RUB to form the VD3-RUB structure in powder form. Solubility of this powder in physiologic solutions of water, gastric or intestinal fluid, stability over time, and dilutability for achieving desired supplementation levels were examined. The VD3-RUB complex structure in water solution was characterised for particle size and shape using dynamic light scattering techniques. VD3 in water solution after filtration was quantified on HPLC. VD3 was practically insoluble in water. However, in the presence of 10% w/v RUB as the botanical solubilizer, VD3 became soluble in water to a concentration of 4,500 µg/mL. This water-soluble concentrate appeared clear and was freely dilutable to a drink containing amounts of VD3 ranging from 15 µg to 100 µg. Particle size analysis indicated the presence of approximately 4 nm spherical particles. HPLC analysis of the water solution detected RUB and VD3. These drinks were stable and remained clear and transparent for at least eight weeks. A packet of water-soluble Vitamin D3 powder was also developed for addition to a glass of water in the amount of 15 µg VD3. The packet, similar to the instant coffee powder, produced an instant Vitamin D drink containing the recommended dietary allowance of 15 µg. The water-soluble VD3 powder was also dissolvable in simulated gastric fluid and intestinal fluid, and stable for at least two hours. This solubility enhancement could aid in absorption and improve oral bioavailability, seen in the work with oily ceramides(1) and insoluble curcumin(2). It is especially advantageous for making drinks as the solubilizer is generally regarded as safe by the US FDA.

Home enteral nutrition (HEN) is a long-term, life-sustaining nutrition therapy for patients unable to consume sufficient food orally. Patients rely on a prescribed, manufactured product to provide their full nutrient requirements, although some patients may have supplementary oral intake. Prescribed enteral nutrition is used as a treatment for malnutrition, but may, in the long-term, cause poor nutrition status. This study aimed to investigate the nutrition status (energy, protein, vitamin D, and selenium) and malnutrition incidence in long-term HEN patients in the Counties Manukau region. In this cross-sectional study, 42 adults on HEN for 4+ weeks under the care of Te Whatu Ora Health New Zealand were analysed. Participants’ enteral and oral feeding regimes were tracked using patient records and five non-consecutive 24-hour recalls. Biochemical markers, body mass index (BMI), body composition (BIA), and nutrition focussed physical findings were evaluated using reference standards and the Global Leadership Initiative on Malnutrition (GLIM) malnutrition criteria(1). Independent t-tests and Mann-Whitney tests compared participants based on their enteral and supplementary oral intakes and adherence to their enteral prescription. Dependent t-tests and Wilcoxon tests evaluated nutrients contributions from various feeding methods and sources. Over half (54.7%, n = 23) relied exclusively on enteral nutrition, but 60% did not achieve their full energy prescription. Compared to requirements based on the Oxford equation and 1g/kg of body weight, energy and protein intake was low in 20% of all participants, mean intake of these participants was 1,242 ± 183 kcal and 57.5 ± 13.5 g respectively. Participants with full enteral intake had a significantly higher vitamin D intake (14.9 µg, P<0.05) than those with supplementary oral intake (11.2 µg, P<0.05). However, those with oral intake had significantly higher intake of selenium, energy, and all the macronutrients than those with sole enteral intake. Vitamin D and selenium intakes were significantly greater in participants obtaining their full prescription than those that did not. No participants had low vitamin D or selenium blood concentrations, however 40% and 38.1% respectively were high. There was a significant relationship between meeting their energy prescription and high plasma selenium. Low BMI, mid arm muscle circumference, and fat free mass index were observed in 47.5%, 40.5%, and 44.8% of participants respectively. This was not statistically significant between groups. Fat mass and waist circumference were significantly higher in participants on full enteral nutrition. According to the GLIM malnutrition criteria, 62.5% (n = 25) of all participants were malnourished. In conclusion, while HEN patients maintain good vitamin D and selenium status, energy and protein malnutrition are evident. The types of food consumed by those with oral intake may be responsible for the differences in nutritional status. Further attention to prescription adherence and nutritional balance from HEN and oral intake is necessary for this vulnerable group.

While it is known that vitamin D deficiency is associated with adverse bone outcomes, it remains unclear whether low vitamin D status may increase the risk of a wider range of health outcomes. We had the opportunity to explore the association between common genetic variants associated with both 25 hydroxyvitamin D (25OHD) and the vitamin D binding protein (DBP, encoded by the GC gene) with a comprehensive range of health disorders and laboratory tests in a large academic medical center. We used summary statistics for 25OHD and DBP to generate polygenic scores (PGS) for 66,482 participants with primarily European ancestry and 13,285 participants with primarily African ancestry from the Vanderbilt University Medical Center Biobank (BioVU). We examined the predictive properties of PGS25OHD, and two scores related to DBP concentration with respect to 1322 health-related phenotypes and 315 laboratory-measured phenotypes from electronic health records. In those with European ancestry: (a) the PGS25OHD and PGSDBP scores, and individual SNPs rs4588 and rs7041 were associated with both 25OHD concentration and 1,25 dihydroxyvitamin D concentrations; (b) higher PGS25OHD was associated with decreased concentrations of triglycerides and cholesterol, and reduced risks of vitamin D deficiency, disorders of lipid metabolism, and diabetes. In general, the findings for the African ancestry group were consistent with findings from the European ancestry analyses. Our study confirms the utility of PGS and two key variants within the GC gene (rs4588 and rs7041) to predict the risk of vitamin D deficiency in clinical settings and highlights the shared biology between vitamin D-related genetic pathways a range of health outcomes.

Prenatal vitamin D deficiency is widely reported and may affect perinatal outcomes. In this secondary analysis of the UK Pregnancies Better Eating and Activity Trial, we examined vitamin D status and its relationship with selected pregnancy outcomes in women with obesity (BMI ≥ 30 kg/m2) from multi-ethnic inner-city settings in the UK. Determinants of vitamin D status at a mean of 17 ± 1 weeks’ gestation were assessed using multivariable linear regression and reported as percent differences in serum 25-hydroxyvitamin D (25(OH)D). Associations between 25(OH)D and clinical outcomes were examined using logistic regression. Among 1089 participants, 67 % had 25(OH)D < 50 nmol/l and 26 % had concentrations < 25 nmol/l. In fully adjusted models accounting for socio-demographic and anthropometric characteristics, 25(OH)D was lower among women of Black (% difference = −33; 95 % CI: −39, −27), Asian (% difference = −43; 95 % CI: −51, −35) and other non-White (% difference = −26; 95 % CI: −35, −14) ethnicity compared with women of White ethnicity (n 1086; P < 0·001 for all). In unadjusted analysis, risk of gestational diabetes was greater in women with 25(OH)D < 25 nmol/l compared with ≥ 50 nmol/l (OR = 1·58; 95 % CI: 1·09, 2·31), but the magnitude of effect estimates was attenuated in the multivariable model (OR = 1·33; 95 % CI: 0·88, 2·00). There were no associations between 25(OH)D and risk of preeclampsia, preterm birth or small for gestational age or large-for-gestational-age delivery. These findings demonstrate low 25(OH)D among pregnant women with obesity and highlight ethnic disparities in vitamin D status in the UK. However, evidence for a greater risk of adverse perinatal outcomes among women with vitamin D deficiency was limited.

Tuberculosis (TB) remains a global leading cause of death, necessitating an investigation into its unequal distribution. Sun exposure, linked to vitamin D (VD) synthesis, has been proposed as a protective factor. This study aimed to analyse TB rates in Spain over time and space and explore their relationship with sunlight exposure. An ecological study examined the associations between rainfall, sunshine hours, and TB incidence in Spain. Data from the National Epidemiological Surveillance Network (RENAVE in Spanish) and the Spanish Meteorological Agency (AEMET in Spanish) from 2012 to 2020 were utilized. Correlation and spatial regression analyses were conducted. Between 2012 and 2020, 43,419 non-imported TB cases were reported. A geographic pattern (north–south) and distinct seasonality (spring peaks and autumn troughs) were observed. Sunshine hours and rainfall displayed a strong negative correlation. Spatial regression and seasonal models identified a negative correlation between TB incidence and sunshine hours, with a four-month lag. A clear spatiotemporal association between TB incidence and sunshine hours emerged in Spain from 2012 to 2020. VD levels likely mediate this relationship, being influenced by sunlight exposure and TB development. Further research is warranted to elucidate the causal pathway and inform public health strategies for improved TB control.