Role of Vitamin D in Innate Immunity to Tuberculosis
Vitamin D DeficiencyTuberculosisThe investigators proposed a pilot study preparatory to developing a randomized trial of vitamin D for the prevention of TB infection. The specific aims are presented below: To recruit subjects, obtain consent, distribute vitamin D supplements to the children in the schools, obtain blood samples and transport them to the United States. To test the hypothesis that daily vitamin D supplementation will increase plasma levels of 25(OH)D, and restore TLR-induced antimicrobial activity in monocytes/macrophages tested in vitro.
Oral Cholecalciferol in Prevention of Type 2 Diabetes Mellitus
PrediabetesVitamin D DeficiencyType 2 diabetes mellitus (T2DM) is a major public health problem .Prevalence of vitamin D deficiency is also high i.e. 78-96% in different groups of population in north India. Observational studies find association between low Vitamin D status and type 2 diabetes mellitus. Prediabetes is a condition that progress to diabetes at a rate of 6-10% per year .There is mechanistic support that vitamin D may influence both insulin secretion and insulin sensitivity and subsequently T2DM incidence. In general, cross-sectional and prospective studies support the role of vitamin D in the prevention of T2DM. This study will be a single blind randomized placebo controlled trial to study the effect of oral cholecalciferol in insulin sensitivity and secretion in adults with prediabetes who are also vitamin D insufficient.
Comparing Different Amounts of Vitamin D Supplementation to Preschool Children Living in Northern...
Vitamin D DeficiencyVitamin D has a range of biological effects of public health relevance. Vitamin D status is assessed on levels of its metabolite 25-hydroxyvitamin D [25(OH)D], where levels < 50 nmol/L indicate insufficiency. Despite studies indicating that the vitamin D intake among Swedish children are significantly below recommendations, little is known of their vitamin D status. The investigators have recently found inadequate vitamin D status in pre-school children living in northern Sweden, especially in dark-skinned children and during the winter months despite vitamin D intakes meeting the recommendations. Overall, 25% of the light skinned and 40% of the dark skinned children had S-25(OH) D <50 nmol/L (Öhlund I, unpublished data). The aim is to examine which amount of vitamin D is needed to maintain or increase S-25(OH)D to ≥50 nmol/L among 97.5% of the participants regardless of skin color or geographic location (northern or southern Sweden). Furthermore the investigators will examine if vitamin D status affects on health markers as bone density, blood pressure, serum lipids, fatty acids, inflammatory and immunological markers and mental wellbeing. Children aged 5-8 years living either northern (Umeå) or southern Sweden (Malmö) will be recruited to this trial during November-December 2012. They will be randomized to a vitamin D supplement of either 10 or 25 g per day, or in Malmö also placebo to be used for three months. The randomization will be stratified according to skin color (light or dark) according to a method using visual inspection and interviews of parents/guardians. The investigators will use a 2×2×2 factorial design to investigate the effects of two different doses of vitamin D (10 µg and 25 µg) in children with dark and light skin color, living in northern (Umeå) and southern (Malmö), Sweden. In order to achieve a moderate difference between groups (effect size 0.25) 20 children per group are required (power> 87%, alpha = 0.05). With an estimated dropout of 10%, a total of 220 children will be included. At baseline, the participants will undergo blood sampling for S-25(OH)D and other biomarkers, blood pressure and anthropometrical measurements, including bone densitometry and body composition using air displacement pletysmography, and the parents will answer a questionnaire on behavioral and emotional problems in the participating child using the Child Behavior Checklist. These measurements will be repeated at follow-up in February-March 2013.
Blue Sky Study: Impact of Milk and Vitamin D for Child Growth and Health
Vitamin d DeficiencyThis intervention study will address the impact of vitamin D fortified milk and vitamin D supplements on the growth, levels of vitamin D, insulin-like growth factor 1, growth hormone, academic attention, respiratory infections, asthma, and flexural dermatitis (a proxy for eczema) of Mongolian children.
Safety of Vitamin D Supplementation in Older Persons
Vitamin D DeficiencyThis study will evaluate the safety over 6 months of two different doses of vitamin D (cholecalciferol) in men and women age 65 and older. It will also evaluate if supplementation with vitamin D improves physical performance.
Controlled Trial of Prenatal Vitamin D3 Supplementation to Prevent Vitamin D Deficiency in Mothers...
Vitamin D DeficiencyThe purpose of this research study is to compare the effects of higher dose vitamin D with commonly recommended dose in pregnant women to see which is better in achieving and/or maintaining sufficient vitamin D blood levels during pregnancy and in newborn infants as well as improving growth in the infant.
Prevention of Vitamin D Deficiency
Vitamin D DeficiencyBreastfed infants living in a northern location (41 degrees N) are at high risk of vitamin D deficiency during winter. This trial is designed to determine how much supplemental vitamin D breastfed infants need to receive in order to remain free of vitamin D deficiency
Vitamin D Supplementation to Prevent Vitamin D Deficiency for Children With Epilepsy
EpilepsyVitamin D DeficiencyTo determine the maintenance dose of vitamin D supplementation required for children with epilepsy to maintain normal vitamin D level.
Preoperative Vitamin D Levels and Respiratory Complications of General Anesthesia
Vitamin D DeficiencyVitamin D deficiency is a commonly observed health problem in the world. With a role in many chronic diseases and especially lung diseases, the importance of vitamin D deficiency in anesthesia management is increased. This research aims to investigate whether there is a correlation between the respiratory complications occurring in patients under general anesthesia and preoperative vitamin D levels.
Vitamin D Supplementation in Estonian Conscripts
Vitamin D DeficiencyMilitary Activity1 moreA longitudinal, double-blinded, randomized, trial, with a 10 month follow-up period will be conducted between July 2021 to May 2022