Vitamin D Effects in Overweight Patients

Study Overview
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Brief Summary
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The purpose of the study is to investigate in overweight patients who are on a telemedically guided weight loss program the influence of a daily vitamin D supplement on weight loss and body composition, selected inflammation markers and biochemical parameters of lipid and glucose metabolism . selected clinical parameters such as blood pressure, heart rate

Detailed Description
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Obese patients are known to have low levels of vitamin D metabolites. There is some evidence that vitamin D and/or dietary calcium may influence energy metabolism and body weight. We therefore perform a prospective controlled trial with 200 overweight (Body mass index 27-29.9 kg/m2) and obese subjects (Body mass index >= 30 kg/m2) who are on a telemedically guided weight loss program. Subjects randomly receive a daily vitamin D supplement or a placebo for 1 year. Participants have to send their body weight data to the study office weekly. In addition, a nutritionist at the study office has to be contacted weekly to receive further support concerning the weight loss program. Dietary records have to be completed monthly. Clinical parameters and blood samples are collected at baseline, and after 6 and 12 months. It is the aim of the study to investigate the vitamin D effects on weight loss and body composition. In addition, possible vitamin D effects on clinical and selected biochemical parameters should be assessed. These parameters include heart rate, blood pressure, inflammation markers, and parameters of lipid and glucose metablolism.

Official Title
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Effects of a Vitamin D (Cholecalciferol) Supplement on Body Composition, Blood Pressure, and Lipid and Diabetes Parameters in Overweight Patients Attending a Telemedically Guided Weight Loss Program

Conditions
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Overweight, Obesity

Intervention / Treatment
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* Dietary Supplement: vitamin D


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Body mass index > 27 kg/m2 Exclusion Criteria: pregnant and lactating women vegetarians patients with renal insufficiency (creatinine > 1.5 mg/dl) History of renal stones and gallstones patients with insulin dependent diabetes mellitus parallel participation in another clinical study missing informed consent subjects with pacemaker implantation

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 70 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: vitamin D oil<br>oil containing vitamin D (Vigantol oil) | Dietary Supplement: vitamin D<br>* 6 drops of a vitamin D containing oil<br>|
| Placebo Comparator: placebo oil<br>oil not containg vitamin D (Migliol oil) | Dietary Supplement: vitamin D<br>* 6 drops of a vitamin D containing oil<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Body Weight From Baseline to 12 Months |  | baseline, 12 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Fat Mass From Baseline to 12 Months |  | baseline, 12 months | 
| Change in 25-hydroxyvitamin D From Baseline to 12 Months |  | baseline, 12 months | 
| Change in Calcitriol From Baseline to 12 Months |  | baseline, 12 months | 
| Change in Parathyroid Hormone From Baseline to 12 Months |  | baseline, 12 months | 
| Change in Triglycerides From Baseline to 12 Months |  | baseline, 12 months | 
| Change in LDL-cholsterol From Baseline to 12 Months |  | baseline, 12 months | 
| Change in C-reactive Protein From Baseline to 12 Months |  | baseline, 12 months | 
| Change in Tumor Necrosis Factor Alpha From Baseline to 12 Months |  | baseline, 12 months | 
| Change in Proinsulin From Baseline to 12 Months |  | baseline, 12 months | 
| Change in Hb A1c From Baseline to 12 Months |  | change from baseline to 12 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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body weight, body compostion, vitamin D, blood pressure