Download or read book Vitamin D and the Lung written by Augusto A. Litonjua and published by Springer Science & Business Media. This book was released on 2012-05-23 with total page 333 pages. Available in PDF, EPUB and Kindle. Book excerpt: Vitamin D deficiency is a worldwide problem and many associations with diseases are being discovered. Recently, there has been an interest in the role that vitamin D plays in the inception and progression of lung disease. Vitamin D and the Lung: Mechanisms and Disease Associations delivers a concise, evidence-based review of the evidence for a role of vitamin D in various lung disorders. Divided into three sections, the first section of the book delivers a review of how vitamin D deficiency emerged in human populations, and gives a perspective on how humans evolved to maximize the efficiency of production of vitamin D. The second section of the book reviews aspects of vitamin D mechanisms on different immune cells, lung tissue, and genetics that have potential impact on lung disease. The third section follows with chapters on associations of vitamin D with the risk for viral infections, asthma and allergies, chronic obstructive pulmonary disease, cystic fibrosis, tuberculosis, and finally, lung cancer with an emphasis on ongoing research and clinical issues and needs for future research in each field. Written by an international group of expert authors, Vitamin D and the Lung: Mechanisms and Disease Associations is an essential text for researchers in the respiratory field and practicing clinicians including internists, pulmonologists, and primary care personnel.

Download or read book The Role of Vitamin D in Pulmonary Function and Lung Gene Expression written by Brian John Reardon and published by . This book was released on 2012 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt: Decline in lung function is a risk factor for chronic obstructive pulmonary disease (COPD). Vitamin D may protect against loss of lung function by modulating inflammation and tissue remodeling. We investigated the association of serum 25-hydroxyvitamin D (25-OH-D) and genetic variants in vitamin D metabolic pathway genes with prognostic measures of obstructive lung disease including forced expiratory volume in the first second (FEV1) and the ratio of FEV1 to forced vital capacity (FEV1/FVC) using data from the Health Aging and Body Composition cohort study of adults aged 70-79. We also obtained the first evidence of differential gene expression in lung epithelial cells associated with serum 25-hydroxyvitamin D in free-living humans. In regression models, there was a significant cross-sectional association of 25-OH-D with FEV1. We detected no association between 25OH-D and rate of FEV1 decline over 10 years. The longitudinal results suggest that vitamin D supplementation in non-deficient individuals is unlikely to prevent decline in lung function in this age range. However, results are also compatible with a beneficial effect of vitamin D earlier in life, which may explain the cross-sectional association of 25-OH-D with lung function. Single nucleotide polymorphisms (SNPs) in vitamin D metabolic pathway genes were tested in linear regression models stratified by race. In African-Americans, rs3886163 and 2 haplotypes in CYP24A1 were associated with FEV1, and rs11168293 in VDR was associated with FEV1/FVC, after correction for multiple testing. Two gene-environment interactions, between serum 25-OH-D and SNPs in RXRA, in European-Americans were significant with false discovery rate (FDR)

Download or read book Vitamin D deficiency is associated with airway remodelling and altered lung structure and function written by Rachel Ee Lin Foong and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The prevalence of vitamin D deficiency is high all over the world and there is now a large body of evidence linking vitamin D deficiency to chronic conditions, including autoimmune, infectious, cardiovascular and respiratory disease. Of relevance to chronic respiratory disease, some studies have shown that vitamin D deficiency is more prevalent in patients with asthma. Lower vitamin D levels are also associated with reduced lung function, increased asthma exacerbations and airway remodelling. In asthma, structural alterations in the lung have origins in early life, and factors that influence lung development may alter lung function and cause an increased susceptibility to disease in the long term. Vitamin D may be a factor affecting lung development, and maternal vitamin D deficiency may therefore contribute to asthma pathogenesis in children. This thesis examines the link between early-life vitamin D deficiency with airway remodelling and lung structure and function outcomes; as well as the role of vitamin D deficiency in chronic allergic airways disease. Specifically, this thesis addresses the hypotheses that 1) whole-life vitamin D deficiency impairs lung structure and function, and causes airway remodelling and airway hyperresponsiveness; 2) impairment in lung structure and function is caused by altered lung development as a result of vitamin D deficiency in utero; 3) vitamin D deficiency alters the expression of genes involved in airway remodelling; and 4) vitamin D deficiency exacerbates respiratory outcomes in chronic allergic airways disease. The development of a physiologically relevant mouse model of vitamin D deficiency, together with the establishment of an in utero and postnatal exposure model allowed for the investigation of early-life vitamin D status on lung structure and function. Vitamin D deficiency caused airway hyperresponsiveness in adult female mice and this was accompanied by an increase in airway smooth muscle mass, as well as smaller lung volume and altered lung structure. In utero vitamin D deficiency was sufficient to cause these changes. The use of an established protocol for development of a chronic asthma model, using the common aeroallergen house dust mite, showed that vitamin D deficiency increased airway hyperresponsiveness and inflammation, but did not increase airway smooth muscle mass. Transcriptome sequencing via RNA-Seq demonstrated that vitamin D deficiency altered gene pathways involved in lung development and inflammation. Midline 1 was further identified as a potential mediator of asthma that is modulated by vitamin D. This study provides evidence that early life vitamin D deficiency has long term impacts on lung health. While postnatal supplementation may reduce inflammation, it may not be sufficient to alter lung structure defects, which are likely to be established early in life. Vitamin D deficiency has the propensity to modulate gene expression and this study has identified potential markers of disease modified by vitamin D. These results add substantially to the growing body of literature which implicates vitamin D deficiency in chronic lung disease and highlights the importance of vitamin D not only in disease, but also in lung development.

Download or read book Vitamin D Interaction with Vitamin A and Lung Cancer written by Ting-Yuan Cheng and published by . This book was released on 2013 with total page 169 pages. Available in PDF, EPUB and Kindle. Book excerpt: Vitamin D inhibits several pathways of lung cancer carcinogenesis and cells in the respiratory tract produce and utilize vitamin D. Vitamin D's functions rely on vitamin D receptor together with retinoid X receptor, which ligands with 9-cis-retinoic acid, a vitamin A (retinol) metabolite. The objectives of this dissertation are to investigate 1) whether high versus low vitamin D intake is associated with lower lung cancer incidence, 2) whether high/excess vitamin A intake attenuates the inverse association of vitamin D intake with lung cancer, and 3) whether vitamin D intake is associated with vitamin D status, represented by serum 25-hydroxyvitamin D concentrations. Data sources were the Women's Health Initiative Clinical Trials and Observational Study (WHI-CT and OS), recruiting postmenopausal women mostly former/never smokers, and the Carotene and Retinol Efficacy Trial (CARET), recruiting male and female current/former heavy smokers and workers with occupational exposure to asbestos. Vitamin D exposure included total vitamin D intake from food and dietary supplements and 1 g calcium+400 IU vitamin D3 daily supplementation from the WHI Calcium/Vitamin D Trial. Vitamin A exposure included total vitamin A intake from food and dietary supplements and CARET's intervention--30 mg beta-carotene+25,000 IU retinyl palmitate daily supplementation (22,500 [mu] g/day Retinal Activity Equivalent [RAE]). Results from the WHI-OS showed that total vitamin D intake was strongly associated with serum 25-hydroxyvitamin D concentrations after adjusting for available covariates and sun exposure variables. The vitamin D intake-lung cancer associations were examined separately in the WHI CT+OS and CARET. High (≥400 IU/day in WHI and ≥600 IU/day in CARET) versus low total vitamin D intake was associated with a lower risk of lung cancer, particularly for non-small cell lung cancer and adenocarcinoma, among never smokers in WHI and former smokers in CARET. The patterns of effect modification of vitamin A intake were heterogeneous according to participants' smoking status. Among current smokers (and CARET former smokers, who generally were heavy smokers before quitting), an inverse association of total vitamin D intake with lung cancer was only observed among those with high total vitamin A intake (≥3,000 [mu] g/day RAE in WHI [P-interaction=0.26] and ≥1,500 [mu] g/day RAE in CARET [P-interaction=0.08]) or receiving the CARET intervention (P-interaction=0.24). However, among WHI participants as a whole, high vitamin A intake (≥1,000 [mu] g/day RAE) may attenuate a protective association of 1 g calcium+400 IU vitamin D3 supplementation with lung cancer (P-interaction=0.09). The difference in smoking between WHI and CARET may contribute to the discrepant findings on vitamin A effect modification. The findings need further confirmation by biomarkers of vitamin A that reflects internal dose and have less measurement error compared to dietary data. This work demonstrates that vitamin D is an important determinant for postmenopausal women and provides important fundamentals for vitamin D and vitamin A in lung cancer prevention.

Download or read book Powerful Medicine written by Lucinda Messer and published by Dog Ear Publishing. This book was released on 2009-12 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Vitamin D deficiency is a world-wide epidemic, with over one billion people at risk for its associated diseases." www.vitamindcouncil.org Powerful Medicine: Vitamin D is the inside scoop on what has become a very real health crisis around the world. Inside these pages you'll find out exactly how vitamin D operates in the body and what happens when it's not available for protection. A deficiency in vitamin D is the main reason we have skyrocketing incidence of Cancer, MS, Diabetes, Osteoporosis, Depression, Season Affective Disorder, Autism, Hypertension and more. And what can healthy levels of vitamin D do for you? To start with, activated vitamin D can: halt tumor growth and reduce tumor size, improve heart health by regulating blood pressure, improve insulin production and regulate blood sugar levels, improve chances of survival from cancer related surgery, keep bones healthy by regulating calcium levels, improve mental health and provide protection from the common cold, viruses and much, much more. By reading this book you are stepping onto a path that will ultimately protect you and your loved ones from the natural consequences of vitamin D deficiency. In light and health, Lucinda Messer, N.D. Dr. Messer is a naturopathic physician and graduate of the prestigious Bastyr University. She has been in private practice for 15 years; specializing in women's health, nutritional and anti-aging medicine. Dr. Messer's writings on anti-aging, the thyroid and natural hormone therapies, have been widely published and she's frequently asked to speak on nutritional medicine. You can find Dr. Messer on the web at www.powerfulmedicine-vitd.com and www.DrLMesser.com. Her co-author Sidse Powell is a freelance writer with an undergrad in biochemistry and alumni of Seattle's The Film School. www.sidsewrites.com. The illustrations and cover were designed by Riley Dickens, a freelance artist with disciplines in film, animation, 2D/3D design, illustration, acrylics, digital paint, and more. www.rileydickens.com.

Download or read book Vitamin C written by Qi Chen and published by CRC Press. This book was released on 2020-01-23 with total page 321 pages. Available in PDF, EPUB and Kindle. Book excerpt: Vitamin C holds a unique place in scientific and cultural history. In this book, a group of leading scientific researchers describe new insights into the myriad ways vitamin C is employed during normal physiological functioning. In addition, the text provides an extensive overview of the following: the rationale for utilizing vitamin C in the clinic, updates on recent uses of vitamin C in cancer treatment through high-dose intravenous therapies, the role vitamin C plays in the treatment of sepsis and infectious disease, management of the ways vitamin C can improve stem cell differentiation, as well as vitamin C use in other important health situations. Features Includes chapters from a team of leading international scholars Reviews the history and recent research on the functions, benefits, and uses of vitamin C Focuses special attention on the way vitamin C can be used in the treatment of cancers Discusses how vitamin C can be employed against infectious disease

Download or read book Vitamin D written by Joyanna Gilmour Hansen and published by . This book was released on 2013 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt: Vitamin D, a pleiotropic hormone essential for calcium homeostasis, has generated widespread interest due to associations with numerous health outcomes. Cross-sectional studies of vitamin D and lung function reported strong, positive associations, but representative, longitudinal population-based studies are lacking, and biological mechanisms are unclear. Lung function decline is the primary characteristic of chronic obstructive pulmonary disease (COPD), the 3rd leading cause of mortality in the United States; given limited treatments to delay progression, identifying preventative approaches is critical. This work aims to elucidate determinants of vitamin D status, and investigate the role of vitamin D as a determinant of lung function. First, we explored genetic and non-genetic determinants of serum vitamin D [25(OH)D] in African Americans. Approximately 25% of 25(OH)D variability was explained by non-genetic factors, and multivitamin supplement use was the strongest predictor. A single nucleotide polymorphism (SNP) in the vitamin D binding protein modified the effect of multivitamin supplement use on 25(OH)D. About 23% of 25(OH)D variability was estimated to be attributable to genetic variation, with replication in a separate cohort. However, the influence of genetic ancestry made an exact estimate impossible; further exploration of genetic determinants of 25(OH)D in African Americans is needed. Second, potential mechanisms for vitamin D-lung health associations were explored through a cross-sectional study of SNPs in 13 candidate vitamin Dresponsive genes. SNPs in SGPP2, a phosphatase in the sphingosine-1-phosphate signaling pathway, were associated with lung function and COPD risk. Further, we identified an association between SNPs in SGPP2 and lung-tissue specific expression of SGPP2. While specific mechanisms remain to be investigated, SGPP2 is a promising vitamin D-responsive candidate gene. Finally, associations between variants in vitamin D metabolic genes, serum 25(OH)D and lung function were explored in the Framingham Heart Study. SNPs in four vitamin D metabolic genes were associated with rate of change in FEV1, but there was no association between 25(OH)D and rate of change in FEV1 in the Third Generation cohort, a group of largely vitamin D sufficient middleaged adults. Future studies should consider the influence of baseline nutritional status and underlying genetic variation on vitamin D-disease associations.

Download or read book Nutrition Immunity and Lung Health Time to Take Center Stage written by Emma Derbyshire and published by Frontiers Media SA. This book was released on 2022-01-21 with total page 107 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Investigating the Immuno modulatory Roles of Vitamin D and Aplha 1 Antitrypsin in Human Lung Diseases written by Hebe Chen and published by . This book was released on 2016 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: These findings suggest an interaction between vitamin D and AA T and support the concept that both are important mediators in the maintenance of respiratory health. Understanding how those mediators exert protective effects in the airways is critical in optimizing therapeutic strategies for AATD, where the only approved therapy has many limitations.

Download or read book Effect of Vitamin D Supplementation on Prevention of Upper Respiratory Tract Infections written by Jing Guo and published by Open Dissertation Press. This book was released on 2017-01-26 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation, "Effect of vitamin D supplementation on prevention of upper respiratory tract infections: a systematic review of randomized controlled trials / y Guo Jing" by Jing, Guo, 郭婧, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: Background The prevention of chronic diseases has always been a major focus in the medical field as a measure to improve public health. As a potential prevention to one of the most common chronic diseases, vitamin D was previously reported to show some signs of positive effect on the prevention of upper respiratory tract infections. Although trials were performed to demonstrate the association between the effectiveness of vitamin D and upper respiratory tract infections in the past few years, the number of randomized controlled trials was limited. Only one systematic review with meta-analysis was carried out to study the effect of vitamin D supplementation on prevention of respiratory tract infections (Charan et al., 2012). Aim A systematic review of the existing evidence was carried out with the aim to examine the effectiveness of vitamin D supplementation as an intervention in prevention of upper respiratory tract infections. Method Studies were selectively chosen based on the inclusion and exclusion criteria. Retrieval of studies was performed and identified from MEDLINE (Ovid) and PUBMED. MeSH terms of "Vitamin D" and "Upper respiratory tract infections" were applied in the search. Only randomized controlled trials were selected. Non-English publications, reviews, discussions, conference papers, and publications with outcomes being not incidence of URTI, were excluded. The quality of each study was evaluated using the Jadad scale (Jadad et al., 1996). Data from the trials was extracted into the meta-analysis, and odds ratios and confidence intervals were used as measures of the association between vitamin D supplementation and incidence of upper respiratory tract infections across studies. Result Five randomized controlled trials were included in this review. In this meta-analysis, the number of events of upper respiratory tract infections in vitamin D group was lower than that in the placebo group (OR=0.53), suggesting that a 47% lower odds of falling in vitamin D groups than in controls. The 95% confidence interval ranged from 0.30to 0.93and did not include 1, suggesting that the effect of vitamin D on prevention of upper respiratory tract infections was significant. However, when the trials were divided into children and adult groups, the results were significantly different. The result of the trials with two children gave an OR of 0.33(95%CI: 0.13, 0.83), meaning a positive effect of vitamin D could be observed in the vitamin D group, compared to the placebo group. Meanwhile, three trials on adults had an OR of 0.78 (95%CI: 0.56, 1.09), which was insufficient to suggest the two groups were different. Conclusion While the positive effect of vitamin D supplementation for the prevention of upper respiratory tract infections is evident on children in this review, it is much less significant on adults due to inconsistencies in the results. Therefore, more research and trials with improved methodologies would be required in the future to increase our understanding and provide more certainty on this matter. DOI: 10.5353/th_b5098550 Subjects: Respiratory infections - Prevention Vitamin D - Health aspects

Download or read book A Systematic Review of Vitamin D for Prevention of Acute Lower Respiratory Infection Among Children written by Tianshu Wu and published by Open Dissertation Press. This book was released on 2017-01-26 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation, "A Systematic Review of Vitamin D for Prevention of Acute Lower Respiratory Infection Among Children" by Tianshu, Wu, 吴添舒, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: Objective: Acute lower respiratory infection (ALRI) is the leading cause of mortality in pediatric group all around the world. Vitamin D has been demonstrated to play a possible role in the prevention of ALRI in children because of its physiological importance in the immune system. This systematic review aims to explore the protective role of vitamin D on ALRIs among children and its preventive effectiveness by synthesizing RCTs. And the other objective is to determine dosage of vitamin D with the best effect by investigating the association of different level of vitamin D supplementation with risk of ALRIs. Methods: Studies were searched through three databases PubMed, ISI Web of Knowledge and Cochran Central Register of Controlled Trials and Cochran Library databases among publication from April2003 to April 2013 with a combination of key terms. Inclusion and exclusion criteria were used to select studies. And then CONSORT guideline and JADAD scale were used to assess quality of these studies. Data on outcome measurements including health outcomes (e.g. incidence of pneumonia and influenza A, duration of recovery of pneumonia and bronchiolitis, the risk of relapse of pneumonia, the number of parent-reported ARIs); and surrogate outcomes (e.g. measuring scores of ATAQ test) were extracted and tabulated. The association with vitamin D level of risk of ALRIs were explored as well. Results: Eight RCTs were found to be relevant and adopted in this systematic review of the 796 identified articles in English or Chinese. The findings were mixed, but most studies suggested vitamin D supplementation reduced risk or illness duration of ALRIs significantly among children with different levels of vitamin D deficiency. Four studies suggested statistically significant risk reduction on incidence of repeat pneumonia (by29%, 95%CI 6% to 46%), parent-reported ARIs (by 48%, 95%CI 11% to 69), influenza A (by 42%, 95%CI 1% to 66%), and asthma exacerbation triggered by ALRIs (P= 0.029), while one study showed an insignificant outcome. For recovery events and hospitalization of ALRIs, three studies suggested statistically significant reduction on recovery time from pneumonia (P= 0.008), severe asthma (P= 0.004) and bronchiolitis (PConclusion: Overall, the evidence is insufficient to conclude that vitamin D supplementation is beneficial to all kinds of children in preventing or assistant treating ALRIs. More number of high quality, large scale and unbiased RCTs should be conducted to confirm the effectiveness of vitamin D among children in Hong Kong and different areas in mainland China. DOI: 10.5353/th_b5098950 Subjects: Vitamin D - Therapeutic use Respiratory infections in children - Prevention

Download or read book Impact of Vitamin D and Vitamin D Binding Protein on the Respiratory Health of Farmers in the French Region of Auvergne written by Hugues François and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent epidemiological studies have found relationship of serum 25-OH Vitamin D (Vitamin D) with respiratory outcomes and lung functions. We look for a relationship of respiratory health with Vitamin D and the Vitamin D-binding protein (VDBP) among farmers from the French region of Auvergne. A cross-sectional epidemiological study was realised between 2009 and 2010 among 359 adults of the FERMA study population. A standardized questionnaire (current allergic nasal and ocular symptoms, current allergic nasal symptoms, current cough, current regular cough and expectoration, current wheezing or whistling, recent shortness of breath, and asthma) was recorded. A lung spirometry wiht bronchodilator test was realised. The serum level of Vitamin D (chemiluminescence technology) and VDBP (by ELISA) were measured. The mean serum level of Vitamin D was 17 ng/mL and of VDBP was 123.73 ng/mL. Current regular cough and expectoration is inversely related wiht Vit D (adjusted Odds Ratio = 0.311,95% CI : 0.103-0.937).Small airways disease (FEF25-75

Download or read book Fetal and Neonatal Lung Development written by Alan H. Jobe and published by Cambridge University Press. This book was released on 2016-04-18 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Lung disease affects more than 600 million people worldwide. While some of these lung diseases have an obvious developmental component, there is growing appreciation that processes and pathways critical for normal lung development are also important for postnatal tissue homeostasis and are dysregulated in lung disease. This book provides an authoritative review of fetal and neonatal lung development and is designed to provide a diverse group of scientists, spanning the basic to clinical research spectrum, with the latest developments on the cellular and molecular mechanisms of normal lung development and injury-repair processes, and how they are dysregulated in disease. The book covers genetics, omics, and systems biology as well as new imaging techniques that are transforming studies of lung development. The reader will learn where the field of lung development has been, where it is presently, and where it is going in order to improve outcomes for patients with common and rare lung diseases.

Download or read book The Effect of Vitamin D Status on Lung Function and Airway Inflammation in Adults in Saudi Arabia and the UK written by Samih Atallah Kokandi and published by . This book was released on 2016 with total page 178 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Respiratory Epidemiology written by Isabella Annesi-Maesano and published by European Respiratory Society. This book was released on 2014-09-01 with total page 308 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the last decade, the volume of research into the pathophysiology and genetics of pulmonary diseases has increased greatly. This has led to the development of new treatments and therapies for many diseases, including lung cancer, asthma and cystic fibrosis. This issue of the ERS Monograph comprehensively demonstrates the developments in respiratory medicine in recent years. It outlines the importance of epidemiology in respiratory medicine, and will prove a methodological tool that will help disease management. It should also be used as an advocacy tool for the sake of public health.

Download or read book Vitamin D and Cancer written by Donald L. Trump and published by Springer Science & Business Media. This book was released on 2010-12-09 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt: Substantial data indicate the broad importance of vitamin D-based signaling in normal human physiology and the broad effects of vitamin D deficiency. Vitamin D may play a role not only in the control of bone and mineral metabolism, but also appears to be involved in immune function, cardiovascular health, thrombosis and vasculogenesis and neuromuscular function. Considerable epidemiologic data demonstrate that low vitamin D serum levels occur very commonly in normal adult populations and that vitamin D deficiency is associated with an enhanced risk of cancer death from lung, prostate, head & neck, colorectal and other gastrointestinal cancers. In addition, preclinical data provide evidence that calcitriol and other active analogues of calcitriol have anti-proliferative, pro-differentiative, pro-apoptotic and anti-angiogenic activity in numerous in-vitro and in-vivo models. It is quite clear that, while it requires high exposure to calcitriol to induce these effects, such exposure can be readily achieved when high dose intermittent therapy is given.

Download or read book Association Between Asthma and Vitamin D in Children Adolescents and Adults written by Selvanayagam John Niruban and published by . This book was released on 2014 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt: Inconsistent results have been reported in studies investigating the relationship between serum vitamin D levels and respiratory outcomes. In this thesis, data from the Canadian Health Measures Survey were used to examine the relationship between serum 25-hydroxy vitamin D [25(OH)D] levels and respiratory outcomes. Children with 25(OH)D levels less than 50 nmol/L and greater than 75 nmol/L had increased risk of current wheeze and reduced cross- sectional changes in lung function with age in comparison to those children with 25(OH)D levels between 50 and 74nmol/L suggesting a U-shaped relationship between 25(OH)D levels and these respiratory outcomes in children. The lower 25(OH)D category was also a significant risk factor for asthma attacks in adolescents and adults. Monitoring of serum vitamin D level may enhance management of respiratory conditions in children, adolescents and adults. Further exploration of this relationship is needed to identify the optimal level of vitamin D for respiratory outcomes.