Obesity
Conditions
Keywords
Prebiotics, Microbiome, Glucose metabolism
Brief summary
The aim of this study is to investigate whether a diet supplemented with two prebiotic fibres induces greater changes in body weight compared to placebo during 12 weeks of energy restriction in an obese/overweight population. The hypothesis is that the fiber-containing dietary supplement will: 1\) Induce greater changes in body weight compared to the placebo group 2) change the gut microbiota composition 3) improve glucose homeostasis 4) decrease serum concentration of triglycerides, total and LDL cholesterol The hypothesis is that the effect of the intervention on weight loss will be partly mediated by the diet-induced changes in the gut microbiota composition.
Detailed description
Prebiotics are nutrients that specifically utilized by the gut microbiota. Beneficial health effects of prebiotics are generally attributed to 1) stimulation of beneficial bacteria and SCFA production, and consequently; improved barrier function, regulation of enteroendocrine peptide secretion and resistance to inflammatory stimuli; 2) modulation of lipid metabolism, possibly by suppression of lipogenic enzymes and thus decreased synthesis of lipoproteins and triglycerides; and 3) increased mineral absorption. Inulin is recognized as a common prebiotic. Fibersol-2 is a resistant starch that has been suggested to induce satiety, when given in a dose of 10 g. Intake of inulin has been shown to induce changes in the microbial abundance and increase production of SCFA19; whereas resistant starch has been shown to improve insulin sensitivity and postprandial glucose AUC20. However, the effects of an intervention with a combination of these two fibers on obesity and body composition during an energy restricted diet have not been addressed. Supplements with other types of fibres in addition to energy restriction have shown additional effects in weight reduction. In this study, the effects of a combination product of two prebiotic fibres on additional weight loss during energy restriction in a placebo-controlled, randomized parallel study with a duration of 12 weeks will be tested. Furthermore, the effects of the fibres on the gut microbial composition, markers of metabolic syndrome (MetS) and glucose metabolism will be tested. The active diet will contain intervention products high in dietary fibre and the placebo diet will contain maltodextrin. The fiber-containing dietary supplements will add approximately 20 g of prebiotic fibres per day, where approximately 10 g will be inulin and approximately 10 g will be resistant maltodextrin. The intervention products and placebo will be consumed as milk. The fiber-containing dietary supplement is expected to induce additional weight loss, compared to placebo and to affect the gut microbiome and markers of metabolic disease.
Interventions
DIETARY_SUPPLEMENTFiber-containing dietary supplement
Effects of fiber-containing dietary supplement on weight loss during energy restriction
DIETARY_SUPPLEMENTPlacebo
Effects of placebo supplement on weight loss during energy restriction
Sponsors
University of Reading
TNO
National Research Council, Spain
University of Copenhagen
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to 60 Years
Healthy volunteers
Yes
Inclusion criteria
* BMI: 28-45 kg/m2 * Non-smoking * Haemoglobin level ≥7 mmol/L
Exclusion criteria
* Use of antibiotics three months prior to study and during the study. If a participant uses antibiotics prior to randomization, the participant will be invited to be re-screened 3 months after the last use of antibiotics, provided that it is realistic to complete the study no later than the scheduled LPLV * Weight change \>3 kg two months prior to study * Blood donation other than for this study \<1 month prior to study and during study. * Participation in clinical trials other than for this \<1 month prior to study and during study * Intensive physical training/ elite athlete (\>10 hours of strenuous physical activity per week) * Unstable medication for dyslipidaemia and elevated blood pressure (the participant must have had a stable dose in the three months prior to study start), and use of systemic glucocorticoids * Medication for T2D * Treatment with metformin * Dietary supplements with pro- and/or prebiotics and/or fibre 6 weeks prior to study * Special dietary regimen (vegetarians, vegans etc.), as evaluated by study staff * Lactose intolerance or allergy to components in the intervention products * Gluten intolerance * Maltodextrin intolerance * Lactation, pregnancy or planning of pregnancy during the study * Gastro intestinal and liver disorders * Chronic inflammation disorders (excluding obesity) * Diagnosed psychiatric disorder including depression requiring treatment * Surgical treatment of obesity and abdominal surgery * Inability, physically or mentally, to comply with the procedures required by the study protocol, as evaluated by the study staff
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Weight loss | Measurements will be performed at baseline and after 12 weeks of intervention | Differences in changes in body weight between the group that receives fiber-containing dietary supplement and placebo group |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Body composition | Measurements will be performed at baseline and after 12 weeks of intervention | Changes in body composition |
| Gut microbiota composition and function | Measurements will be performed at baseline and after 12 weeks of intervention | Changes in gut microbiota composition and function (faecal samples) assesed by metagenomics |
| Inflammatory markers | Measurements will be performed at baseline and after 12 weeks of intervention | Changes in concentration of inflammatory markers |
| SCFA concentration | Measurements will be performed at baseline and after 12 weeks of intervention | Changes in faecal concentration of short chain fatty acids |
| Lipidomics and bile acids | Measurements will be performed at baseline and after 12 weeks of intervention | Changes in concentration of lipids and bile acids in blood and faecal samples |
| Metabolomics | Measurements will be performed at baseline and after 12 weeks of intervention | Analyses of metabolites in blood, urine and fecal samples |
| Weight loss | Measurements will be performed at baseline and after 12 weeks of intervention | Interaction between differences in changes in body weight between the group that receives fiber-containing dietary supplement and placebo group and each of baseline fasting glucose, baseline fasting insulin and baseline microbiome composition (e.g. enterotype). |
| Lipid metabolism | Measurements will be performed at baseline and after 12 weeks of intervention | Analyses of lipids in blood samples |
| Glucose metabolism | Measurements will be performed at baseline and after 12 weeks of intervention | Glucose and insulin homeostasis |
Other
| Measure | Time frame | Description |
|---|---|---|
| Gene expression | Measurements will be performed at baseline and after 12 weeks of intervention | Measurements of gene expression in of selected genes |
| Epigenetics | Measurements will be performed at baseline and after 12 weeks of intervention | Measurements of epigenetic markers in biological samples |
| Blood pressure | Measurements will be performed at baseline and after 12 weeks of intervention | Blood pressure measured by an automated blood pressure monitor |
| Liver markers | Measurements will be performed at baseline and after 12 weeks of intervention | Measurement of markers of liver health |
| Physical activity | Measurements will be performed at baseline and after 12 weeks of intervention | Measurement of physical activity, as assessed by Actigraph monitors |
| Appetite regulation | Measurements will be performed at baseline and after 12 weeks of intervention | Markers of appetite regulation |
Countries
Denmark
Outcome results
None listed