View clinical trials related to Vitamin D Deficiency.
Filter by:Children and adolescents with psychiatric illnesses who are treated with medications called second generation antipsychotic agents (SGA) often gain excessive weight during their treatment with these medications. This weight gain may result in the development of features of the metabolic syndrome or frank diabetes mellitus. There is no consensus on the best way to prevent these complications. The investigators' hypothesis is that daily vitamin D supplementation in these patients will result in decreased levels of the markers of metabolic syndrome with associated reduction in waist circumference.
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.
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.
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.
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.
Fibroblast growth factor 23 (FGF23) is a new hormone which controls phosphate and vitamin D levels in humans. Excess FGF23 is associated with an increased risk of death in patients with chronic kidney disease. In this study the investigators are investigating the effects of different forms of vitamin D on FGF23 levels in the blood in order to increase our understanding of how this important hormone works.
Vitamin D is a natural nutrient. A little comes from our normal daily diet. Most of it comes from our skin after we have been in sunlight. If we have darker skin, we make less vitamin D. Vitamin D balances the calcium in our body. If our vitamin D levels get too low, it can cause health problems. It may increase our chance of getting high blood pressure or diabetes. Another problem we may have if our vitamin D levels are low is that our blood vessels may not work normally. These are important health problems for anyone. Because African Americans have darker skin, they are more likely than most other racial/ethnic groups to have low vitamin D levels. This study will look at treating African Americans with low vitamin D levels. The goal of this study is to see how vitamin D helps blood vessels work. The investigators will do this study in African Americans who are overweight, have high blood pressure and have low vitamin D levels. The investigators will see if getting the vitamin D level to a normal value will improve how blood vessels work. The dose of vitamin D that will be given in this study is a high dose that is given to people with low vitamin D levels.
The purpose of this study is to answer the following questions: Does vitamin D increase calcium absorption, bone mass and muscle mass and function in women past menopause who have mildly low vitamin D levels? Do these benefits require prescription-strength vitamin D, or is an over the counter vitamin D dose enough?
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.
The purpose of this study is to determine if 14-19 year old African American adolescents are able to take a daily vitamin D supplement daily for about 4 months and how well a daily dose of 400 IU or 2000 IU vitamin D supplement raises their vitamin D blood level.