Effect of Glucomannan Supplementation on Body Weight in Overweight and Obese Children

Study Overview
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Brief Summary
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Glucomannan (GNN), a water-soluble dietary fiber derived from the plant Amorphophallus konjac, is marketed for weight reduction. The exact mechanisms by which GNN might exert its actions are unclear. Nonetheless, it has been shown that GNN slows gastric emptying by forming a viscous gel of large volume, which increases the feeling of satiety. Current evidence on the effectiveness of GNN for weight reduction is sparse, and well-designed trials performed in children are needed to assess the efficacy of this modality. We aim to systematically evaluate the efficacy of GNN consumption for the management of overweight and obesity in children.

Detailed Description
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Methods and analysis Children aged 6 to 17 years with overweight and obesity (based on the WHO growth criteria) will be randomly assigned to receive GNN or placebo (maltodextrin) (both at a dose of 3 g/day) for 3 months and will be followed up for 3 months. Prior to the intervention, all children will receive dietetic advice, and they will be encouraged to engage in physical activity. The primary outcome measure will be the BMI-for-age z-score difference between the groups at the end of the intervention.

Official Title
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Effect of Glucomannan Supplementation on Body Weight in Overweight and Obese Children: A Randomized Controlled Trial

Conditions
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Obesity, Overweight

Intervention / Treatment
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* Dietary Supplement: Glucomannan
* Dietary Supplement: Maltodextrin


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: age 6-17 years; overweight or obesity based on the WHO (World Health Organization) growth charts/references (>+1 standard deviation [SD] or >+2 SD, respectively) Exclusion Criteria: drug therapy for a chronic disease (including drugs that influence appetite or body weight); type 1 or 2 diabetes; history of surgical treatment of obesity; participation in another program for treating obesity during the project and/or 3 months prior to recruitment; secondary causes of obesity; pregnancy.

Ages Eligible for Study
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Minimum Age: 6 Years
Maximum Age: 17 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

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: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Glucomannan<br>Glucomannan orally, 3g/day (in three divided doses), for 12 weeks | Dietary Supplement: Glucomannan<br> <br> * Other names: Amorphophallus konjac;|
| Placebo Comparator: Maltodextrin<br>Maltodextrin orally, 3g/day (in three divided doses), for 12 weeks | Dietary Supplement: Maltodextrin<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| BMI-for-age z-score difference | Baseline versus end of the intervention | 0-12 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Body composition | Whole body fat, central body fat, fat-free mass (grams) assessed by a dual energy X-ray absorption (DXA) | 0-13 weeks | 
| BMI-for-age z-score difference | Baseline versus end of the follow-up | 0-24 weeks | 
| Proportion of participants with dyslipidemia | Proportion of participants with dyslipidemia from baseline to week 12 and week 24 (mean change, SD) | At baseline, 12 weeks and 24 weeks | 
| Proportion of participants with impaired fasting plasma glucose (FPG) | Proportion of participants with impaired fasting plasma glucose (FPG) from baseline to week 12 and week 24 (mean change, SD). | At baseline, 12 weeks and 24 weeks | 
| Energy intake (kJ/d) | Based on self-written, 3-day food records | At baseline and at week 12, week 24. | 
| Physical activity | Measured using an accelerometer | at baseline and at week 12 | 
| Adverse events |  | 0-12 weeks | 
| Blood pressure (systolic and diastolic) | The mean change from baseline to week 12, and week 24 | Baseline, week 12, 24 weeks. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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glucomannan, obesity, children, overweight, adolescents, treatment