Impact of Ketogenic Diets in Preventing Relapse in Obesity Management

Study Overview
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Brief Summary
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Low-carb ketogenic diets have become extremely popular because of large weight loss in the short-term. Yet their potential benefits in preventing long-term weight regain have not been assessed in large scale studies. The aim of this study is to determine the effect of a low-carbohydrate (CHO) ketogenic diet, compared with an isocaloric balanced diet, on the maintenance of weight loss. The secondary aim is to investigate the impact of both diets on appetite. Adults with obesity (30<BMI<40 kg/m2), will first undergo 4 weeks of a very-low energy diet aimed at inducing 5-10% weight loss and then will be randomized to two different weight maintenance diets for 1 year. One will be a low-CHO ketogenic diet (50 g CHO/day) plant-based (e.g. with less animal protein and more plant-based), and the other a diet following the Norwegian Health Directorate recommendations. Only conventional foods will be used in both diets.

Official Title
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Evaluation of the Efficacy, Feasibility, and Safety of Ketogenic Diets in Preventing Relapse in Obesity Management

Conditions
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Obesity

Intervention / Treatment
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* Behavioral: Ketogenic weight loss maintenance diet
* Behavioral: Isocaloric balanced weight loss maintenance diet


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: weight stable over the last three months (<2 kg) not currently dieting to lose weight inactive lifestyle (less than 150 min of physical activity weekly. Given that some of the variables of interest have been shown to be affected by the phase of menstrual cycle in normally ovulating women, namely appetite and resting metabolic rate, only women taking oral contraceptives, with regular menstrual cycles or post-menopausal will be included in the study Exclusion Criteria: pregnancy breast-feeding drug or alcohol abuse within the last two years clinically significant illness including diabetes, gastrointestinal (particularly cholelithiasis), kidney (GFR <60) or liver disease, osteoporosis (T-score <-2.5) and osteopenia (T-score <-1.5) treatment with antiosteoporotic drug depression or other psychological disorders eating disorders milk intolerance current medication known to affect appetite/metabolism or induce weight loss. a planned surgery during the study period participating in another research study

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Ketogenic weight loss maintenance diet<br>The ketogenic weight loss maintenance group will undergo in a ketogenic diet (50 g CHO/day) plant-based for 1 year. | Behavioral: Ketogenic weight loss maintenance diet<br>* The ketogenic weight loss maintenance group will undergo in a ketogenic diet (50 g CHO/day) plant-based for 1 year.<br>|
| Experimental: Isocaloric balanced weight loss maintenance diet<br>The isocaloric balanced weight loss maintenance group will undergo in a diet following the standard Norwegian Health Directorate recommendations for 1 year. | Behavioral: Isocaloric balanced weight loss maintenance diet<br>* The isocaloric balanced weight loss maintenance group will undergo in a diet following the recommendations from the Norwegian Health Directorate for 1 year.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Body weight regain | Body weight will be measured at baseline, at week 5, at 6 months, and at 1 year | Body weight changes at 1-year intervention | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Fasting lipid profile | Blood sampling in fasting to measure lipid profile (plasma concentration of total cholesterol, triglycerides, high-density lipids (HDL), low-density lipids (LDL) at baseline, at 6 months, and at 1 year | Lipid profile changes at 1-year intervention | 
| Bone mineral density | Bone mineral density will be measured by Dual-energy X-ray absorptiometry (DXA) at baseline, at 6 months, and at 1 year | Bone mineral density changes at 1-year intervention | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Diet, Ketogenic, Weight Loss, Body Weight