Modified Atkins Diet for Overweight and Obesity

Study Overview
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Brief Summary
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The aim of the study is to investigate dynamic changes in biochemical metabolism, gut microbiome and its metabolites among overweight and obese participants while they are on a modified Atkins Diets.

Detailed Description
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The mechanisms of obesity are complex, involved in genes, environment, life style, and systemic and adipose tissue inflammation. Dysbiosis of gut microbiome is considered to make a difference in obesity. On the other hand, both long-term and short-term dietary interventions can induce changes in the body composition and structure and function of gut microbiome. However, it is not really clear how gut microbiome changes along with weight loss in overweight or obese. In the present study, investigators aim to characterize the gut microbiome among overweight or obese participants on a modified Atkins diets. The stool and blood samples were collected by an interval of every 5% and 10% of weight loss, respectively. Data collecting mainly covers: 1) body composition analysis ; 2) obesity related biochemical metabolism; 3) measurement of gut microbiome using metagenome and 16S rRNA sequencing techniques; 4) metabolomics of serum and gut microbiome; 5) measurement of physical activity and diets using questionnaires.

Official Title
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Longitudinal Profiling of Gut Microbiome in Overweight or Obese Participants on a Modified Atkins Diet: a Prospective Cohort Study

Conditions
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Overweight or Obesity

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 18-55 years old; BMI > 23.9kg/m2; being willing and able to receive guidelines to a modified Atkins diet; signed informed consent. Exclusion Criteria: patients with serious physical and mental diseases (including cardiovascular and cerebrovascular diseases, liver and kidney diseases, respiratory diseases gastrointestinal diseases, mental diseases, etc.); patients with malignant tumor; pregnant and lactating women; those with recent relocation plans.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 55 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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| weight loss group<br>Dynamic changes in body composition, biochemical metabolomics and gut microbiome will be reported among overweight and obese patients. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Dynamic changes of gut microbiome | The stool sample will be collected by an interval of each 5% weight loss that participants experienced. Fecal microbiota will be analyzed by 16S rRNA gene sequencing technique. | 36 months | 
| Dynamic changes in faecal metabolomics | For participants achieving each 10% weight loss, targeting metabonomics will be applied to identify the abundances of faecal metabolites (e.g. short-chain fatty acids, amino acids and carbohyrates) using validated mass spectrometry methods. | 36 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Dynamic changes of body mass index | Weight and height will be combined to report BMI in kg/m^2. | 36 months | 
| Dynamic changes of body fat | As a body composition parameter, body fat will be analyzed by body composition automatic analyzer for each participant every 10-20 days. | 36 months | 
| Dynamic changes of muscle mass | Muscle mass will be analyzed by body composition automatic analyzer for each participant every 10-20 days. | 36 months | 
| Dynamic changes of blood lipids | For participants achieving each 10% weight loss, intravenous serum will be collected and the parameters which can reflect the lipids metalism (such as triglyceride, total cholesterol, low density lipoprotein cholesterol, high density lipoprotein cholesterol ) will be measured by automatic biochemical analyzer. | 36 months | 
| Dynamic changes of fasting blood glucose | For participants achieving each 10% weight loss, intravenous serum will be collected and fasting blood glucose will be measured by automatic biochemical analyzer. | 36 months | 
| Dynamic changes of homocysteine | For participants achieving each 10% weight loss, intravenous serum will be collected and homocysteine will be measured by automatic biochemical analyzer. | 36 months | 
| Dynamic changes of blood pressure | For participants achieving each 10% weight loss, blood pressure will be measured by the standard electronic sphygmomanometer. | 36 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Obesity, Gut Microbiome, Body composition, modified Atkins Diet, Overweight