Active clinical trials for "Vitamin D Deficiency"

This is a randomised, double-blind, double-dummy, multicentre, dose-ranging clinical trial in subjects with vitamin D deficiency or insufficiency. Its general objective is to determine the efficacy and safety of different doses of calcifediol soft gelatin capsules (SGCs) compared to placebo.

In addition to its effect on maintaining calcium homeostasis and mineralization of bone, vitamin D has been linked to play a pivotal role in different medical conditions including type 2 diabetes mellitus. Vitamin D plays a major role in both insulin secretion and decreasing the insulin resistance hence has a major impact on glucose tolerance. This study is designed to determine the non-skeletal effects of vitamin D in improving the glucose tolerance in type 2 diabetic patients by decreasing the insulin resistance

This study is to determine the amount of vitamin D required for a very low birth weight infant to reach vitamin D sufficiency and achieve optimal calcium health and bone growth.

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 assumption has been that 1,25(OH)2D is solely responsible for calcium absorption. That has been one of the presumed causes of hyperparathyroidism in chronic kidney disease (CKD) (low 1,25(OH)2D leads to decreased calcium absorption, which increases parathyroid hormone release in compensation). Replacing 1,25 D directly has been the goal with using 1,25D or its analogues in CKD. There is very little data concerning use of native vitamin D or 25(OH)D in CKD, although autocrine functions in extrarenal tissues would use 25(OH)D. The latest KDIGO guidelines do recognize the autocrine role of vitamin D, but have no data on outcomes or doses or optimal levels to guide them and so have made a blanket recommendation to treat 25D levels in CKD by general healthy population guidelines. This project focuses on an outcome (calcium absorption) that may be impacted by optimizing 25D status in renal patients. The investigators will assume for this project that a level of 25D > 32 ng/ml is optimal in CKD patients as in a healthy population. A secondary outcome is to quantify calcium absorption in CKD patients with and without vitamin D repletion and to quantify systemic 1,25D levels. This may clarify the roles 25D and 1,25D play in calcium absorption.

The importance of vitamin D (VitD) in the prevention and treatment of human health conditions has gained increased attention in recent years. As a result, medical providers of all categories are screening clinical VitD status frequently, yet become challenged with how to best advise patients regarding repletion of VitD status, i.e. which form of VitD replacement is most effective. It has been recognized that to achieve significant effects - serum concentrations >30ng/ml (75 nmol/ml) - it is necessary, as well as safe, to recommend substantially higher doses than were previously thought sufficient. These higher doses can be easily achieved orally. This clinical trial aims to compare absorption of three available forms of this fat-soluble vitamin, due to the potential differences in absorption of different preparations. High-quality powdered, chewable and lipid-emulsified VitD are readily available as supplements, yet these have not been systematically compared. This three-arm, randomized clinical trial will compare the difference in serum 25-hydroxycholecalciferol (25-OH)D concentration between the three arms at baseline and after random administration of one of the three VitD preparations for 12-weeks at a dosage of 10,000 IU VitD per day. The investigators hypothesize that the three forms of vitD will result in an equivalent increase in serum 25OHD.

In the past two decades, the role of vitamin D has extended beyond bone health to encompass a wide range of biological activities important to physical function in older adults. A growing body of evidence now shows that circulating 25-hydroxyvitamin D (25(OH)D) levels < 75 nmol/L (< 30 ng/mL)) are associated with physical impairments such as reduced walking speed and impaired balance as well as falls. Older adults are at risk for low levels of 25-hydroxyvitamin D because of reduced exposure to ultraviolet B radiation, reduced efficiency of previtamin D synthesis in the skin, and low dietary intake. Although data from the National Health and Nutrition Examination Survey (NHANES) 2000-2004 indicate that frank vitamin D deficiency (serum 25(OH)D < 25 nmol/L [10 ng/mL]) is rare in the U.S. (5% or less), vitamin D insufficiency (serum 25(OH)D < 75 nmol/L [30 ng/mL]) is prevalent (~75%) among older adults. Older home-bound adults are a vulnerable subgroup of older adults for poor dietary intake and nutritional health, nutrition-related health conditions, and functional decline and disability. The primary goal of this pilot study is to assess the feasibility of a partnership with Senior Services of Forsyth County to address vitamin D insufficiency in home-bound older adults receiving home-delivered meals. A secondary goal is to obtain preliminary data on the effectiveness of vitamin D supplementation on improving vitamin D levels and reducing falls.

To learn if there is a connection between low vitamin D level and hardening of the arteries.

Obesity is an increasing health problem with numerous metabolic complications. Vitamin D deficiency is common in obesity, and in epidemiological studies vitamin D deficiency has been linked to metabolic complications, such as type 2 diabetes, insulin resistance and cardiovascular disease, as well as myopathy, osteoporosis and depression. In obesity, a low grade inflammation is present in the fat tissue, thereby releasing inflammatory molecules to the blood stream. In cell line studies as well as small clinical studies vitamin D has been shown to have the ability to reduce inflammation and cell growth. In the present study the investigators wish to investigate the effect of vitamin D on fat-, muscle and bone metabolism. 30 healthy obese subjects will be treated with cholecalciferol 175 micrograms daily for 6 months and will be compared with 30 healthy obese subjects treated with placebo. The investigators hypothesize that restoring vitamin D levels in vitamin D deficient obese subject will reduce inflammation and thereby reduce obesity-related complications. The effect will be evaluated as follows: Levels of circulating inflammatory markers will be examined in blood samples collected prior to and after treatment. Effects on fat- and muscle metabolism will be evaluated in fat- and muscle samples taken before and after treatment. Effects on fat distribution will be evaluated by MRI scan before and after treatment. Effects on insulin sensitivity will be evaluated by hyperinsulinaemic euglycaemic clamp performed on a subgroup of subjects with impaired fasting glucose. Effects on bone marrow density will be evaluated by DEXA scans before and after treatment. Effects on quality of life and depression score will be evaluated by questionnaires used before and after treatment.

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?