Active clinical trials for "Vitamin D Deficiency"

The purpose of this study is to evaluate the absorption of dietary supplement of vitamin D3 (cholecalciferol), through the variation of 25 (OH) D levels, as the fat content of the meal associated with the administration of the supplement.

Purpose of this study is to investigate the effect of treatment with vitamin D3 (cholecalciferol) compared with placebo in a trial including chronic kidney disease patients with vitamin D deficiency.

There is suggestive evidence that vitamin C and vitamin D deficiency may increase blood pressure across the range of blood pressures from normal to elevated. Information about this relationship is inadequate in part because of the rarity of individuals with subclinical vitamin C and D deficiency. The investigators have observed subnormal to deficient plasma vitamin C and 25-hydroxyvitamin D levels in a large proportion of patients under active treatment in the investigators' hospital. The clinical implications of widespread hypovitaminosis C and D are unknown. In this randomized prospective comparison trial the investigators will measure vitamin levels and blood pressure in clinically stable acutely hospitalized patients with a wide range of diagnoses, and expected to remain in the hospital for at least 7 more days. The investigators will examine for an inverse relationship between baseline vitamin level and blood pressure across the range of blood pressures. Consenting patients will be randomized to receive vitamin C (500 mg twice daily) or vitamin D (1000 IU twice daily) for as long as 10 days. Blood pressure will be re-measured every 2 days and vitamin levels re-measured on the last study day. Treatment courses of at least 5 days will be considered sufficient for analysis. The hypothesis is that either treatment will reduce blood pressure in patients whose baseline systolic blood pressure is 110 or more; the investigators will also examine whether the reduction in blood pressure with treatment is proportional to the increase in the circulating vitamin level with treatment.

This is an open label, single center, randomized, active comparator controlled study, comparing the effects of vitamin D replacement using oral ergocalciferol versus paricalcitol on parathyroid hormone (PTH) levels in patients with stage 3 and 4 CKD and vitamin D deficiency or insufficiency. The purpose of this study is to determine which of these two approaches is more successful.

In recent years, vitamin D has been shown not only to be important for bone and calcium metabolism but also for homeostasis of critical tissues involved in vascular disease in patients with diabetes. Epidemiological studies indicated the high prevalence of vitamin D deficiency among Type 2 DM patients and suggest an increased risk of cardiovascular disease and hypertension with low vitamin D levels. The objective of this proposal is to evaluate the effects of vitamin D replacement on blood pressure control and vascular disease in vitamin D deficient hypertensive patients with diabetes

Vitamin D is available in two forms, vitamin D2 and vitamin D3. It has previously been assumed that these two forms maintain blood vitamin D equally. However, this may not be the case. This study will evaluate whether D2 and D3 produce equal elevation of blood vitamin D. Additionally, it will evaluate whether once per month vitamin D dosing is as effective in maintaining blood vitamin D levels as daily dosing.

There are numerous indications for a relation between low serum levels of 25(OH)D and blood pressure, lipid levels, frequency of infections and tendency towards depression. Whether it is a causal relationship it is not known, and can best be studied with a vitamin D intervention. The investigators hypothesis is that supplementation with a high dose vitamin D (40.000 IU per week) will have a beneficial effect on these parameters.

The purpose of this study is to determine the effectiveness and safety of maternal and infant vitamin D supplementation as a function of ethnicity and latitude in the prevention of vitamin D deficiency in the breastfeeding mother-infant pair. The findings of this study will generate important new information for health care professionals and policy makers with regard to vitamin D requirements and the potential benefit to both mother and infant

Administration of vitamin D 50,000 units once monthly will: Maintain serum 25-OH vitamin D above 20 ng/ml Reduce falls Increase calcaneal BMD Reduce bone turnover Be well tolerated: volunteers will not develop hypercalcemia Improve performance on a swallowing quality of life questionnaire

When people eat a meal, some, but not all of the calcium in that meal is absorbed, that is, moved into the bloodstream. When the skin is exposed to sunlight during summer months, Vitamin D is made there and then modified into more active forms by the liver and kidneys. These more active forms of Vitamin D improve calcium absorption. Many adults living in the U.S. have little or no sun exposure and are low in Vitamin D. A single dose of 100,000 IU of Vitamin D3 has been used both as empiric treatment for Vitamin D deficiency as well as in controlled trials without risk of raising blood calcium to dangerous levels.This study is to determine the serum levels of Vitamin D and 25-hydroxyvitamin D (vitamin D after it has been modified by the liver) that can be expected when Vitamin D3 is given as a single oral dose of 100,000 IU.