Obesity & Overweight
Conditions
Keywords
Polydextrose, Dietary Fiber, Functional Gummies, Overweight, Obesity, Weight Management, Weight Loss, Satiety, Appetite, Body Composition, Placebo-Controlled Trial, Randomized Clinical Trial
Brief summary
Overweight and obesity are common conditions that increase the risk of metabolic and cardiovascular diseases. Polydextrose is a type of dietary fiber that may help increase feelings of fullness by influencing natural hormones involved in appetite regulation. It may also improve postprandial glycemic responses and modulate the gut microbiota. However, evidence for its effectiveness in weight management remains limited. The purpose of this study is to evaluate the efficacy and safety of functional gummies containing polydextrose compared with placebo for weight management in adults with overweight or obesity. Participants will be randomly assigned to receive either polydextrose or placebo gummies for 24 weeks, together with standardized dietary and physical activity recommendations. The primary objective is to compare the percentage change in body weight over 24 weeks between participants receiving polydextrose gummies and those receiving placebo. The study will also evaluate appetite and satiety, body composition, waist circumference, metabolic parameters, quality of life, gastrointestinal symptoms, and the safety and tolerability of the study product. The study hypothesis is that daily intake of polydextrose gummies for 24 weeks will lead to a greater reduction in body weight than placebo and may improve subjective feelings of appetite and satiety in adults with overweight or obesity.
Detailed description
Overweight and obesity are major public health challenges associated with an increased risk of type 2 diabetes, cardiovascular disease, metabolic dysfunction, and reduced quality of life. In this context, dietary and lifestyle interventions represent a first-line strategy for the management of overweight and the prevention of associated comorbidities, as they can induce favorable metabolic changes and improvements in vascular risk factors even when weight loss is modest. Within this framework, modulation of appetite and energy intake through functional ingredients such as dietary fibers has gained particular interest. Polydextrose is a soluble, partially fermentable dietary fiber that resists digestion in the upper gastrointestinal tract and undergoes partial fermentation by the colonic microbiota. Proposed mechanisms of action include delayed gastric emptying, stimulation of satiety-related gut hormones such as glucagon-like peptide-1 (GLP-1), modulation of postprandial glycemic responses, and favorable effects on gut microbiota composition. However, evidence for its effectiveness in weight management is still limited and inconsistent, and further research is needed to confirm its clinical benefits. This study is a single-center, randomized, double-blind, placebo-controlled, parallel-group clinical trial. Adult participants with overweight or class I-II obesity will be randomly assigned to receive either functional gummies containing polydextrose or matching placebo gummies for 24 weeks. Randomization will be performed using a block randomization procedure stratified by age, sex, and body mass index (BMI). Participants, investigators, and study personnel involved in clinical assessment will remain blinded to treatment allocation throughout the study. Both study groups will receive the same standardized lifestyle recommendations, including dietary counseling based on healthy Mediterranean dietary principles and guidance to maintain habitual physical activity throughout the intervention period. Participants will also receive specific instructions to avoid consuming additional foods containing polydextrose outside the study products in order to minimize potential confounding and maintain treatment blinding. Compliance will be reinforced throughout follow-up using participant diaries, structured interviews, and product accountability procedures. Study gummies will be consumed approximately 15 to 30 minutes before each main meal (breakfast, lunch, and dinner), and the daily dose will be gradually increased during the first weeks according to gastrointestinal tolerability, up to a maximum of three gummies before each meal in participants with good tolerability. Participants will complete one baseline visit, one telephone follow-up at Week 4, and two on-site follow-up visits at Weeks 12 and 24. The primary objective is to evaluate the effect of polydextrose gummies versus placebo on percentage change in body weight over 24 weeks. Secondary objectives include assessing changes in appetite and satiety ratings, body composition (including fat mass and lean mass), waist circumference, and several metabolic parameters such as fasting glucose, glycated hemoglobin (HbA1c), fasting insulin, lipid profile, liver enzymes, and blood pressure. Quality of life and gastrointestinal tolerability will also be evaluated using validated questionnaires. Clinical assessments will be performed under standardized conditions to reduce measurement variability. The study has been designed to determine whether daily supplementation with polydextrose functional gummies provides additional benefits beyond standardized lifestyle advice for body weight reduction while maintaining an acceptable safety and tolerability profile. The results are expected to contribute evidence regarding the potential role of polydextrose as a nutritional strategy for weight management in adults with overweight or obesity.
Interventions
Participants in the experimental group will consume the polydextrose gummies before each main meal (breakfast, lunch, and dinner) for 24 weeks. The daily dose will be gradually increased during the first week from 1 gummy before each meal to 2 gummies before each meal. From week 4 onwards, participants with good gastrointestinal tolerability will increase to 3 gummies before each meal, while those with acceptable tolerability will remain at 2 gummies before each meal. Participants with poor tolerability will be withdrawn from the study. The gummies will be taken approximately 15 to 30 minutes before meals, preferably with a glass of water. All participants will also receive standard dietary and physical activity recommendations.
Participants in the control group will consume matching placebo gummies without polydextrose before each main meal (breakfast, lunch, and dinner) for 24 weeks. The daily dose will be gradually increased during the first week from 1 gummy before each meal to 2 gummies before each meal. From week 4 onwards, participants with good gastrointestinal tolerability will increase to 3 gummies before each meal, while those with acceptable tolerability will remain at 2 gummies before each meal. Participants with poor tolerability will be withdrawn from the study. The gummies will be taken approximately 15 to 30 minutes before meals, preferably with a glass of water. All participants will also receive standard dietary and physical activity recommendations.
Sponsors
Study design
Masking description
This is a randomized, double-blind, placebo-controlled study. Individual unblinding will only be permitted when knowledge of the assigned treatment is essential for the clinical assessment or medical management of a serious adverse event or a suspected unexpected serious adverse reaction, as specified in the study protocol.
Intervention model description
Participants will be randomly assigned in a 1:1 ratio to one of two parallel groups receiving either polydextrose gummies or matching placebo gummies for 24 weeks. Both groups will follow the same stepwise dose-escalation schedule based on gastrointestinal tolerability, together with standardized dietary and physical activity recommendations.
Eligibility
Inclusion criteria
* Adults aged 18 to 70 years. * Body mass index (BMI) between 25 and 39.9 kg/m² (overweight or obesity class I-II). * Stable body weight (no change greater than 3%) in the 3 months before joining the study. * Usually eat at least 2 meals per day. * Able and willing to follow the study procedures for 24 weeks, attend all scheduled visits, and complete the required records. * Willing and able to sign the informed consent form.
Exclusion criteria
* Type 2 diabetes with glycated hemoglobin (HbA1c) greater than 7%, type 1 diabetes, or type 2 diabetes treated with multiple daily insulin injections. * Treatment with sodium-glucose co-transporter-2 (SGLT2) inhibitors for diabetes, heart failure, or chronic kidney disease. * Uncontrolled thyroid disease \[thyroid-stimulating hormone (TSH) outside the normal range\] or recent changes in thyroid medication in the last 3 months. * Significant gastrointestinal disease (such as severe irritable bowel syndrome, Crohn's disease, or ulcerative colitis). * History of bariatric surgery. * Liver cirrhosis. * Advanced chronic kidney disease (stage IV-V). * Following a very low-calorie diet (less than 800 kcal/day). * Alcohol dependence or heavy alcohol use that, in the investigator's opinion, could affect the study. * Current or recent eating disorder. * Planning to start or recently started a specific weight-loss diet different from the one recommended by the study endocrinology service. * Currently taking or having taken in the last 3 months medicines that affect appetite or body weight (such as anorectic drugs, GLP-1 receptor agonists, chronic corticosteroids, antipsychotics, or fiber supplements). * Pregnancy or breastfeeding. * Women of childbearing potential who are trying to become pregnant or plan to become pregnant during the study. * Known allergy or intolerance to any ingredient of the study gummies. * History of severe gastrointestinal problems with fermentable fibers.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Body Weight | Baseline and Week 24 | Percentage change in total body weight from baseline to week 24, calculated as \[(weight at week 24 - baseline weight) / baseline weight\] × 100. Body weight will be measured in kilograms using a calibrated scale under standardized conditions. Negative values indicate weight loss, whereas positive values indicate weight gain. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Subjective Appetite and Satiety Scores | Baseline and weeks 4, 12, and 24 | Change in subjective feelings of hunger and fullness assessed using a 10-point Visual Analog Scale (VAS), where 0 indicates "no hunger" / "not full at all" and 10 indicates "maximum hunger" / "extremely full". Higher scores indicate greater hunger or greater satiety, depending on the item. |
| Fat Mass | Baseline and week 24 | Change in fat mass measured in kilograms and as a percentage of total body weight by bioelectrical impedance analysis (BIA). Body composition will be assessed under standardized conditions, including fasting, consistent hydration, the same time of day, and use of the same device. Negative values indicate a reduction in fat mass. |
| Lean Body Mass | Baseline and Week 24 | Change in lean body mass measured in kilograms and as a percentage of total body weight by bioelectrical impedance analysis (BIA). Body composition will be assessed under standardized conditions, including fasting, consistent hydration, the same time of day, and use of the same device. Positive values indicate an increase in lean body mass. |
| Body Mass Index (BMI) | Baseline and week 24 | Change in body mass index (BMI), calculated as weight (kg) divided by height (m) squared. Weight will be measured under standardized fasting conditions. Height will be measured at baseline. A negative change indicates a reduction in BMI. |
| Waist Circumference | Baseline, week 12, and week 24 | Change in waist circumference measured in centimeters using a standardized protocol. A negative change indicates a reduction in waist circumference. |
| Plasma Glucose | Baseline, week 12, and week 24 | Change in fasting plasma glucose measured in mg/dL after an overnight fast. A negative change indicates a reduction in fasting glucose levels. |
| Glycated Hemoglobin (HbA1c) | Baseline, week 12, and week 24 | Change in HbA1c measured as a percentage. A negative change indicates improvement in long-term glycemic control. |
| Fasting Insulin | Baseline, week 12, and week 24 | Change in fasting insulin measured in µU/mL after an overnight fast. A negative change indicates a reduction in fasting insulin levels. |
| Lipid Profile | Baseline, week 12, and week 24 | Change in total cholesterol, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, and triglycerides measured in mg/dL in fasting conditions. A negative change indicates a reduction in total cholesterol, LDL cholesterol, and triglycerides. For HDL cholesterol, a positive change indicates improvement. |
| Liver Enzymes | Baseline, week 12, and week 24 | Change in alanine aminotransferase (ALT), aspartate aminotransferase (AST), and gamma-glutamyl transferase (GGT) measured in U/L in fasting conditions. Reductions indicate improvement in liver enzyme levels. |
| Systolic and Diastolic Blood Pressure | Baseline, week 12, and week 24 | Change in systolic and diastolic blood pressure measured in mmHg under standardized conditions. A negative change indicates a reduction in blood pressure. |
| Quality of Life Scores | Baseline and week 24 | Change in quality of life assessed using the 12-Item Short Form Health Survey (SF-12) questionnaire. Scores are transformed to physical and mental component summaries, with higher scores indicating better quality of life. |
| Gastrointestinal Symptoms Scores | Baseline, week 4, week 12, and week 24 | Change in gastrointestinal symptoms assessed using the Gastrointestinal Symptom Rating Scale (GSRS) questionnaire. Higher scores indicate more severe gastrointestinal symptoms. |
Countries
Spain