Active clinical trials for "Vitamin D Deficiency"

Poor vitamin D status is very common in African Americans. Periodontitis (gum disease) are shown to be related to theincreased risk of cardiometabolic diseases. Vitamin D is freely available and cheap supplement that has shown beneficialeffect in the immune system regulation and maintenance of the cardiovascular health. In this study The investigators hypothesize thatvitamin D supplementation for 16 weeks in African Americans with periodontitis will result in clinical improvement in theirgum health as well as their cardiometabolic risk profile

Vitamin D receptors are expressed in activated different immune cells. It is not known, which immune cell type is targeted by exogenous vitamin D. Here, vitamin D-deficient individuals will receive once 100.000 I.U. vitamin D3 either intramuscular or subcutaneous in a double-blind placebo controlled setting. Immune cells will be monitored from the blood over time.

The role of vitamin D deficiency in female reproduction remains controversial. Early retrospective studies were inconsistent regarding the effect of serum 25-OH vitamin D levels on pregnancy rates in women undergoing in vitro fertilization (IVF), whereas two retrospective studies postulated that vitamin D deficiency may negatively affect pregnancy rates with an effect mediated through the endometrium. Taking into account that knock-out experiments have shown that vitamin D receptor null mice not only experience uterine hypoplasia but also impaired folliculogenesis, it might be hypothesized that vitamin D deficiency may have a detrimental effect on female ovarian reserve. This may be further supported by previous reports demonstrating that serum 25-OH Vitamin D levels correlates with antimullerian hormone (AMH) levels in women of advanced reproductive age. The aim of this study is to examine through a large set of prospectively recruited infertile women whether serum 25-OH-Vitamin D levels is related with the 2 most widely accepted biomarkers of ovarian reserve: serum AMH levels and antral follicle count (AFC).

The relationship of Vitamin D levels in children and young adults to atherosclerosis.

This study evaluates the effect of Vitamin D3 supplementation in healing rate of tibia fractures in adult patients with low vitamin D. Half of participants will receive Vitamin D3 supplementation while the other will receive placebo.

The purpose of this study is to determine if there is correlation between Vitamin D deficiency and spinal disease/spinal fusion surgery.

The purpose of this study is to determine the association between serum 25-hydroxyvitamin D and HbA1c levels in diabetic patients with chronic kidney disease. The investigators hypothesized that serum 25-hydroxyvitamin D levels were negatively correlated with HbA1c levels.

Vitamin B12 deficiency can cause severe problems with the blood, nerves, brain and psychological well-being. Ironically, our modern methods for the control of diabetes mellitus can actually contribute to vitamin B12 deficiency. This is because the diabetic medication "metformin", low-cholesterol diets lacking in meats (a natural source of vitamin B12) and the use of powerful anti-gastric medication can all reduce the natural absorption of vitamin B12 from the diet, especially in elderly people with diabetes. There is both a high prevalence of vitamin B12 deficiencies and falls among the elderly with type 2 diabetes mellitus and the investigators hypothesize that B12 deficiency contributes directly and significantly to falls in elderly diabetics through impaired muscle strength, gait and balance. This study therefore proposes to investigate the association between vitamin B12 deficiency and fall risk among diabetic elderly patients (older than 65 years) in the polyclinic setting by assessing muscle strength, balance and walking speed. The predictors of vitamin B12, folate, homocysteine and vitamin D levels will also be explored in this study. If the hypothesis is right, this would be of public health importance & can lead to further studies that can change the way we treat diabetes by reducing falls in our elderly diabetics through the screening for, prevention and treatment of B12 deficiency.

Athletes and active individuals have been identified as an at-risk group for a low vitamin D status, specifically those residing in countries of higher latitude (such as the United Kingdom). This especially applies to those who train indoors for their sport, this is because Vitamin D is primarily produced following skin exposure to ultraviolet B (UVB) exposure. Vitamin D is essential for the maintenance of optimal bone and musculoskeletal health. It has also been suggested to play a role in the prevention of illness incidence, such as in upper respiratory tract infections (URTI). More recent research has indicated that an improved Vitamin D status may also play a role in enhancing exercise performance. Therefore, having a poor vitamin D status could negatively impact athletic training and competition. The purpose of this study is to evaluate the prevalence of vitamin D deficiency in university athletes and inactive controls in spring and autumn. During this study the subjects will be asked to visit the labs on two occasions, at the beginning of the study for baseline measurements, and again on two occasions at the end of the study. Participants will have the following outcomes assessed: Sport performance (vertical jump height, muscular strength and aerobic fitness), peripheral Quantitative Computed Tomography (pQCT) scan of the bone mineral composition of the tibia, total body composition via Dual Energy X-ray Absorptiometry (DEXA),total and hip/femoral head bone mineral density and content to assess fracture risk via DEXA. Serum 25(OH)D levels (≈15ml of whole blood will be collected for these measurements. Dietary intake using self-reported food diaries. In addition illness and injury incidence will be recorded daily throughout the study in a booklet provided to the participants.Throughout the trial, the participants will be contacted via telephone/ email on a monthly basis to discuss any issues and maintain good communication.

Vitamin D deficiency is a risk factor for mortality but existing data are limited by missing standardization of laboratory methods for 25-hydroxyvitamin D (25[OH]D). In a European consortium of eight cohort studies we use protocols of the Vitamin D Standardization Program (VDSP) to obtain standardized 25(OH)D data. Individual participant data (IPD) meta-analyses using a one step procedure will be performed to study associations of original and standardized 25(OH)D with all-cause, cardiovascular, and cancer mortality.