View clinical trials related to Vitamin D Deficiency.
Filter by:The purpose of this study is to examine the effects of Vitamin D supplementation on the reasons (mechanisms) underlying the development of type 2 diabetes, metabolic syndrome (high blood pressure, cholesterol, diabetes, body weight/obesity), muscle weakness and wasting (sarcopenia), and impaired physical function (poor balance and walking) associated with vitamin D deficiency and osteopenia/osteoporosis (bone loss). The investigators obtain vitamin D through our diet and sunlight, and its conversion to active vitamins in the liver and kidneys promotes the intestinal absorption of calcium and regulation of bone growth. Therefore, vitamin D deficiency has been known for years to lead to weakened bones (osteopenia and osteoporosis). However, more recently, studies show vitamin D deficiency is associated with a number of other diseases, including type 2 diabetes, muscle weakness, frailty, and the metabolic syndrome. It has also been associated with cognitive impairment. Diabetes affects multiple organ systems including the heart, kidneys, musculoskeletal and nervous system. The possibility that vitamin D deficiency is linked to the development of type 2 diabetes, metabolic syndrome, muscle weakness and wasting (sarcopenia) and osteopenia/osteoporosis, and that vitamin D supplementation decreases the risk for these diseases, provides a relatively easy/accessible and inexpensive model of preventive therapy to decrease the incidence of these diseases. In addition, it is likely that genetic (inherited) factors play a role, but the relationship of these genes to these metabolic abnormalities have not been elucidated. Understanding the role of Vitamin D in health will allow us to translate these findings into therapy.
Specific Aim 1: To compare effects of Vitamin D supplementation to usual care on symptoms in women transitioning to early postmenopause and determine the associated effect size in order to conduct a power analysis for a future RCT. Hypothesis: Vitamin D insufficient women in early postmenopause who are randomized to supplementation, titrated to achieve sufficiency for 2 months, will have fewer symptoms including hot flashes, mood, and musculoskeletal complaints than women randomized to usual care. Specific Aim 2: To compare effects of Vitamin D supplementation to usual care on body composition (by dual-energy x-ray absorptiometry [DXA] and by weight, BMI, waist to hip ratio) in overweight/obese women transitioning to early postmenopause and determine the associated effect size for a power analysis for a future RCT. Hypothesis: Vitamin D insufficient women in the menopausal transition randomized to supplementation, titrated to achieve sufficiency for 9 months, will improve DXA body composition (less total body and abdominal fat), compared to women in usual care, who will have increased body weight, including total and abdominal fat. Specific Aim 3: To estimate the proportion of overweight/obese middle-aged women who achieve sufficiency by 1 month versus 2 or more months and to determine if achieving sufficiency by 1 month varies by baseline characteristics. Hypothesis: About 80% of participants will achieve sufficient Vitamin D level by 1 month. Those who need more than 1 month for sufficiency will have lower baseline levels and higher initial BMI.
Study hypothesis: High-dose vitamin D leads to a shorter hospital stay in critically ill patients Vitamin D deficient patients will be randomized to receive either 540,000 IU cholecalciferol or placebo.
The purpose of this study is to determine the capability to absorb calcium as a measure of the sufficient levels of Vitamin D. Calcium absorption will be measured at baseline and after vitamin D3, by dual calcium isotope technique using stable isotopes in post menopausal women between the ages 50 and 70yrs. Subjects will have a screening visit, first and final visits. Subjects will be randomly assigned to a placebo or daily doses of vitamin D3. The specific aim of this study is to determine the level of vitamin D that will maximize the absorption of calcium and establish the relationship between the administered calcium dose and the actual absorbed calcium dose versus administered dose of Vitamin D and the serum levels of Vitamin D.
the study aims to messure the vitamin D levels in medical staff in the hospital. The physicians in the course of their internship who work indoors and work many night shifts have limited sun exposure in all seasons. Nursing staff who work shifts and work indoors are at the same risk of liltle sun exposure. The study addresses the amount of sun exposure, assessed by a sun exposure questioner, age, gender,work load related to number of shifts in the physicien group and in nursing group the job percentile we also adress religion (clothing cover)as a factor.
Background: Vitamin D is vital throughout pregnancy and lactation for both maternal and infant health. Health Canada recommends women take the AI of 5ug/day of vitamin D during pregnancy, however, it is unknown how much vitamin D is necessary to ensure both mother and baby reach a vitamin D serum concentration of 25OHD>75nmol/L.
This is a feasibility study to examine the treatment with Metformin, vitamin D with calcium supplement for insulin resistance in obese, black, female teens. The association of low vitamin D levels and decreased insulin sensitivity has been established. Thus, the specific aims of this study are: Specific aim 1: To examine the effect of an 8-week treatment with vitamin D and calcium supplementations on diabetes-related risk factors in obese, black, female teens. Hypothesis 1a: In obese, black, female teens with both insulin resistance and vitamin D deficiency, treatment with vitamin D and calcium supplementation will significantly improve measures of insulin resistance and sensitivity (as determined by the homeostatic model assessment for insulin resistance and whole body insulin sensitivity index measures) when compared to controls not receiving vitamin D and calcium. Hypothesis 1b: In obese, black teen females with both insulin resistance and vitamin D deficiency, treatment with vitamin D and calcium supplementation will significantly improve measures of cardiovascular disease (decreased BMI and improved triglycerides and LDL) when compared to controls not receiving vitamin D and calcium. Specific aim 2: To determine if the addition of Metformin to the 8-week treatment with vitamin D and calcium supplementations improves diabetes-related risk factors in obese, black, female teens. Hypothesis 2a: In obese, black, female teens with both insulin resistance and vitamin D deficiency, treatment with Metformin, vitamin D, and calcium supplementation will significantly improve measures of insulin resistance and sensitivity (as determined by the homeostatic model assessment for insulin resistance and whole body insulin sensitivity index measures) when compared to standard of care or treatment with vitamin D with calcium supplementation alone while controlling for dietary intake of vitamin D and calcium. Hypothesis 2b: In obese, black, female teens with both insulin resistance and vitamin D deficiency, treatment with Metformin, vitamin D, and calcium supplementation will significantly improve measures of cardiovascular disease risk (as determined by the decreased BMI, improved triglycerides and LDL) when compared to standard of care or treatment with vitamin D with calcium supplementation alone while controlling for dietary intake of vitamin D and calcium.
Background: Vitamin D plays a key role in calcium absorption in the gut and in skeletal development. Vitamin D deficiency is common, affecting an estimated one billion people worldwide, including developed countries. Vitamin D deficiency causes rickets, the most common non-communicable disease of childhood. Rickets causes poor growth and skeletal deformities and, at its most severe, seizures and death. Recent data suggest that children with rickets have an increased risk for developing diabetes mellitus. Screening for vitamin D deficiency is not commonly done. It is generally diagnosed only after symptoms of rickets have developed. Prevention and treatment is simple and inexpensive. Hence, early detection of vitamin D deficiency through screening would be beneficial. Studies are urgently needed to validate such screening tests. Calcium balance is tightly regulated in the body and calcium loss in the urine (measured by the urine calcium-to-creatinine ratio) is a sensitive indicator of reduced calcium absorption, such as in vitamin D deficiency. Objective and Hypotheses. The objective of this study is to evaluate the urine calcium-to-creatinine ratio as a noninvasive and inexpensive screening test for vitamin D deficiency. Our hypotheses are 1) that the urine calcium-to-creatinine ratio correlates with blood vitamin D levels in infants and toddlers at risk for vitamin D deficiency and 2) that this test can be used to screen for vitamin D deficiency. Potential Impact. A validated screening tool would allow for the detection of vitamin D deficiency before the development of rickets, decreasing the morbidity and mortality of this common disease.
The purpose of this study is to evaluate how Vitamin D affects endothelial function, inflammation, lipids, insulin resistance, vitamin D levels, and PTH.
Study will look at baseline Vitamin D levels, calcium, albumin, liver enzymes, testosterone, osteocalcin, urine N telopeptides, bone mineral density, nutritional assessment and physical activity assessment of boys with hemophilia A or B (ages 2-20 yrs). Patients with low vitamin D levels will receive therapeutic doses of Vitamin D. At end of one year follow up studies will be repeated.