OBJECTIVE: Vitamin D deficiency is prevalent worldwide. While vitamin D deficiency’s role on caries development has been long suggested, it has yet to be confirmed. The aim of this study was to investigate the association between vitamin D level and coronal and root caries in the U.S. METHODS: This study analyzed National Health and Nutrition Examination Survey 2001-2004 data for individuals 6-65 years old. Vitamin D 25(OH)D serum levels were defined according to the Endocrine Society guideline into: Sufficient >75nmol/L, Insufficient 51-75 nmol/L and Deficient < 50 nmol/L. Descriptive and bivariate analyses were conducted on coronal dental caries (DMFT and dft) by serum 25(OH)D level. Multiple regression models were conducted controlling for confounding. Descriptive, regression models, and survival analysis were conducted to assess the relationship between total vitamin D intake and root caries among men (48-93 years) using the Dental Longitudinal Study (DLS) data. Total vitamin D intake was classified according to the Institute of Medicine definition: <400IU/day, 400-800IU/day and >800IU/day. RESULTS: Children (6-11Y) with insufficient levels of vitamin D (50-75 nmol/L) have marginally higher odds of having dental caries experience in their primary teeth compared to those with sufficient serum levels (OR=1.3, p=0.067). No significant associations were found between DMFT and vitamin D serum level before and after controlling for confounding (P>0.05). Cross-sectional analysis of the DLS baseline data showed that higher total vitamin D intake is associated with higher level of root caries (OR=1.2, P=0.011). Repeated measure regression analysis of multiple cycles of DLS data, however, showed that vitamin D total intake was not significantly associated with the level of root caries. Survival analysis also showed no association (P=0.89). CONCLUSION: The results suggest that there is no significant association between vitamin D levels and coronal or root caries in permanent teeth. In contrast, lower serum vitamin D levels might be associated with higher caries levels in primary teeth. The results of this study, while adding new information, provide inconclusive evidence of the association between vitamin D and dental caries. Further investigation is needed to deepen our understanding of the role of vitamin D on dental caries development. / 2018-09-28T00:00:00Z

Vitamin D inadequacy is highly prevalent among pregnant women worldwide. Inadequacy or deficiency of vitamin D can lead to adverse outcomes during pregnancy such as pre-eclampsia, gestational diabetes, and caesarian section. A systematic review and meta-analysis were conducted to examine the effectiveness of vitamin D supplementation on serum vitamin D status during pregnancy in randomized controlled trials (RCTs). A search was conducted in PubMed, Scopus, ProQuest, EBSCO, Cochrane CENTRAL Database of Controlled Clinical Trials, PsycINFO, CINAHL, and Google Scholar, in addition to searching reference lists in published reviews. A comprehensive list of RCTs of vitamin D status and supplemental use in pregnancy was compiled. The random effects model was used to determine a summary effect size using pre/post means and standard deviations of serum vitamin D levels from intervention and control groups. Sixteen RCTs indicated a large effect size (d = .849, 95% CI .607 – 1.001, p < .001). Serum vitamin D concentration at delivery was higher with vitamin D supplementation, and thereby the metabolic outlook was favorable for the mother and newborn. Heterogeneity of the meta-analysis was significant (Q = 344.418, p < .001); the I-squared statistic showed moderate heterogeneity (61.89%), which warranted subgroup analysis to identify possible sources of variation among the studies. Moderators for subgroup analysis included vitamin D dosages, use of a placebo, use of multivitamins in addition to vitamin D, duration of interventions, age, low or adequate baseline vitamin D status, trimester when supplementation was started, country where the RCT was conducted (USA/UK/AUS versus other countries), and blinded versus non-blinded RCTs. Subgroup analysis only demonstrated a significant impact on heterogeneity from the trimester moderator (p < .001). Women who began vitamin D supplementation during the first trimester had a higher effect size and improved vitamin D status compared to those who began supplementation in the second or third trimester. Since pregnant women with vitamin D inadequacy or deficiency are more susceptible to complications, routine examination of vitamin D status should be conducted in pregnant women.

Vitamin D deficiency is considered to be a pandemic with implications for compromised bone health and other chronic diseases. Few studies have examined vitamin D status in college-aged individuals where prevention of future health consequences is still possible. Serum vitamin D 25(OH)D status and vitamin D intake were examined in 98 college students ages 18-29 years during winter. BMI was classified as < 25and 25 or greater. Race was categorized as Caucasian or other. Overall, 69.5% had suboptimal serum vitamin D levels, <30ng/mL. Only 8 students (8.2%) met the EAR (400 IU) per day for vitamin D intake. t tests were used to determine if there were significant differences in serum vitamin D level and dietary intake based on gender, race and BMI. Significant differences were found in serum vitamin D level when compared by gender and race. Females tended to have a higher serum vitamin D level than males. Those representing minorities had lower serum vitamin D levels than Caucasians; One hundred percent of the minority students had suboptimal serum vitamin D levels. Based on these findings, dietitians should increase efforts to target college-aged individuals in educational programming related to factors affecting vitamin D synthesis, vitamin D intake, and health consequences of suboptimal vitamin D status, particularly in winter. Consideration should be given to vitamin D fortification of foods that meet the preferences of today’s consumer.

Bakgrund: Vitamin D finns i två olika former, det animaliska D3 (kolekalciferol) och det vegetabiliska D2 (ergokalciferol). Det har rått olika åsikter bland läkarkåren och allmänheten om vilken av de två formerna som är mest potent för att höja 25(OH)D-statusen i blodet, det värde som mäts för att avgöra vitamin D-halten i kroppen. Då vitamin D-brist är vanligt förekommande bland befolkningen i Norden är det viktigt att veta vilken form som har bäst effekt och som därför bör användas för att behandla och förebygga vitamin D-brist. Det har även betydelse för veganer som inte äter det animaliska D3, där rekommendationen kanske behöver ändras. Syfte: Syftet med studien var att ta reda på om det finns någon skillnad i potensen av D2 respektive D3 för att höja 25(OH)D-statusen i blodet och i så fall, att hitta möjliga orsaker till denna skillnad. Metod: Sex relevanta vetenskapliga originalartiklar, som har undersökt effekten av D2 vs. D3 på 25(OH)D-statusen i blodet, hittades i databasen PubMed. Studierna genomfördes mellan 2008 och 2017. Studiedeltagarna var vuxna friska människor. Resultat: Fyra av studierna pekade på att D3 var mer effektivt än D2 för att höja 25(OH)D-statusen. En studie kom fram till att det inte fanns någon skillnad i potensen mellan D2 och D3 och en studie visade att D2 var mer effektivt jämfört med D3 när det gällde daglig behandling med låga doser men att D3 uppvisade bättre effekt vid behandling med höga doser med två eller fyra veckors avstånd. Slutsats: Majoriteten av studierna visade en bättre effekt av D3 än D2 för att höja 25(OH)D-nivåer i blodet. De blandade resultaten samt det begränsade antalet studier och deltagare gör att det inte är möjligt att kunna komma fram till en tydlig slutsats. / Background: Vitamin D comes in two different forms, D3 from animals (cholecalciferol) and D2 from plants (ergocalciferol). There has been different opinions among physicians and the general public about which of the calciferols is more potent to raise 25(OH)D-levels in the blood, which is the value that is measured to determine the vitamin D-status in the body. Since vitamin D deficiency is common among the people of the Nordic countries it is important to know which form has the best effect and should be used to treat and prevent vitamin D deficiency. Furthermore, it is relevant for vegans who do not eat the animalic D3, where recommendations might have to be changed. Aim: The aim of the study was to find out if there were differences in potency of D2 vs. D3 to raise 25(OH)D status in the blood and if so, to find possible explanations for those differences. Methods: Six relevant original articles that examined the effect of D2 vs. D3 on 25(OH)D status in the blood, were found in the database PubMed. The studies where published between the years 2008 and 2017. The participants were healthy adults. Results: Four of the studies suggested that D3 is more effective than D2 in order to raise the 25(OH)D status. One study concluded that there is no difference in the effectiveness of D2 vs D3 and one study showed that D2 is more effective than D3 when it comes to daily treatment but that D3 has a better effect than D2 when treatment happens on a two or four weekly basis with large doses. Conclusion: Most of the articles suggested a better effectiveness of D3 than D2 to raise 25(OH)D levels in the blood. However, besides the mixed results, the number of studies and participants was too small to come to a clear conclusion.

No description available.

Vitamin D is derived through the action of solar ultraviolet B radiation on skin and from a limited number of natural food sources, fortified foods and supplements. It is well known that vitamin D plays an active role for calcium and phosphorus absorption but there is also growing evidence of an association between vitamin D insufficiency and various chronic diseases. Middle Eastern populations are known to be at risk of vitamin D deficiency due to a diet low in vitamin D and low sunshine exposure. Obesity is also a risk factor since vitamin D is sequestered in body fat. This thesis examined dietary intake of vitamin D, obesity and other risk factors for deficiency in Middle Eastern people in the UK. A questionnaire based survey was undertaken with 242 Middle Eastern respondents. A total of 85% of the sample was estimated to have a vitamin D intake <5 µg/d. Other risk factors for vitamin D insufficiency included covering skin from sunlight (84% females); low use of supplements (18.5%) and being overweight or obese (49% males and 44% females). Vitamin D intake was lowest in those with primary (1.8 µg/d) and secondary school (2.1 µg/d) education compared to higher education (3.6 µg/d). The survey was followed by dietary assessment of 28 Iraqi adults using repeat 24 hour recalls. The results concurred with the survey: mean intake of vitamin D was (3.2±4.4 µg/d) and 78.5% were overweight or obese. Finally, overweight participants were recruited to observe the effect of fat loss on vitamin D status. Serum 25(OH)D concentrations was measured in Middle Eastern (n=12) and Caucasian adults (n=24). Firstly seasonal changes were observed between October and January (with no weight loss). Then participants were advised on weight reduction to observe the effect of fat loss on serum 25(OH)D. Vitamin D deficiency (<25 nmol/l) was observed in 67% of the Middle Eastern group in October increasing to 92% in January. Of the 36 participants, only 17 lost ≥1kg of fat mass between January and April. No difference was found in serum 25(OH)D between those that lost fat mass and those that did not, and no correlation was found between the amount of fat lost and change in 25(OH)D. In the total sample, there was a negative association between serum 25(OH)D and waist circumference and waist-hip ratio, but no correlation was found between 25(OH)D and fat mass, thus indicating a relationship with visceral fat stores rather than total fat mass.

Introduction: Adequate calcium and vitamin D are needed for maternal and fetal health. Many pregnant women are not consuming enough calcium and are at high risk for vitamin D deficiency. Objectives: To 1) investigate the nutrition-related knowledge, opinions, and clinical practices of family physicians (FPs) towards prenatal calcium and vitamin D; and 2) determine the prevalence of meeting a predefined cut-off serum 25-hydroxyvitamin D concentration ([25-OHD]) for vitamin D sufficiency (≥ 75 nmol/L) in a cohort of pregnant women with gestational diabetes mellitus (GDM). Methods: Part 1: 500 surveys were mailed out to randomly selected FPs across Manitoba. Part 2: data were collected via retrospective chart review of 35 pregnant women with GDM attending a teaching hospital in Winnipeg, Manitoba between January 1, 2010 and December 31, 2013 and having one serum [25-OHD] measurement during their pregnancy. Results: Approximately one-third of FPs are discussing calcium and vitamin D requirements and supplements with their prenatal patients. The top three perceived barriers to delivery of calcium and vitamin D advice were more urgent issues, lack of time, and forgetting to do so. The mean serum [25-OHD] was 52.5 ± 24.1 nmol/L (range 14-109 nmol/L). Over half of women (51.4%) were vitamin D deficient ([25-OHD] < 50 nmol/L), and 28.6% of women were insufficient ([25-OHD] 50-74 nmol/L). Conclusions: Physicians would benefit from more training in nutrition. Multiple barriers exist that prevent FPs from providing calcium and vitamin D advice. Women with GDM have a high prevalence of vitamin D deficiency in our study. / February 2016

M.Sc. / Tuberculosis, of which the causative agent is Mycobacterium tuberculosis, presents itself as a serious health problem globally, especially in Africa. Susceptibility to this infectious disease is influenced by the virulence of the strain of mycobacteria, environmental factors, and genetic variation within the host. The Vitamin D Receptor gene or VDR has been identified as a candidate gene for TB susceptibility. This gene codes for the VDR protein that mediates the biological actions of the active form of vitamin D. Vitamin D has been shown to impair growth of Mycobacterium tuberculosis in human monocytes and macrophages. Vitamin D also provides a link between Toll-like receptor activation and the antibacterial responses of innate immunity in its production of cathelicidin. The VDR protein is a transcription factor that mediates the effects of the active form of vitamin D. Vitamin D has an immunomodulatory role and variations in the VDR gene may result in variations in the functioning of the VDR protein, and hence variations in response to infection. The VDR gene includes the largely non-coding 5’ regulatory region exons 1a-1f and the coding exons 2-9. As a result of increased awareness of the heritability of gene expression and reports of disease associations with VDR promoter region variants, the focus of the research described in this dissertation was the regulatory region of the VDR gene. Polymorphisms that occur within the regulatory region were viii investigated, as were the effects these polymorphisms may have on gene expression, influencing host susceptibility to tuberculosis, with an emphasis on African populations. VDR polymorphisms have been shown to be involved in susceptibility to tuberculosis, particularly the FokI SNP in exon 2, BsmI and ApaI in intron 8 and the synonomous TaqI in exon 9. However, results have been inconsistent. SNPs shown to be associated with TB may serve as markers of truly functional SNP with which they are in linkage disequilibrium (LD). The majority of these association studies involve single nucleotide polymorphisms (SNPs) found in the introns or are silent mutations in the coding exons. Variations in the 5’ regulatory region have been shown to affect gene expression, in particular if they influence the binding sites of transcription factors.

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Purpose: This is a pilot study to determine if there is a relationship between vitamin D deficiency and the development of early childhood caries (ECC). Methods: Serum 25(OH) vitamin D, parathyroid hormone and calcium were measured from children with ECC, who presented for dental rehabilitation under general anesthesia. Samples were obtained from caries free controls examined during a well-child medical check. Parents from both sample sizes filled out a questionnaire consisting of 22 questions regarding the child and parent’s medical and dental history as well as socioeconomic background. Results: ECC patients were found to have deficient serum levels of 25(OH) vitamin D and calcium compared to caries free controls. Conclusions: This study observed a difference in 25(OH) vitamin D levels between the two groups. Due to limited sample size and confounding variables contributing to ECC, a definitive relationship between vitamin D deficiency and ECC cannot be made at this time.