Effect of Oligofructose on Appetite in Overweight Subjects

Study Overview
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Brief Summary
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This study seeks to look into the effects of oligofructose supplementation on appetite, energy intake, and body weight and body composition in overweight subjects. Compared to a placebo product (cellulose) oligofructose is hypothesised to suppress hunger and thereby reduce food intake moderately leading to a decrease in body weight.

Detailed Description
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Appetite regulation plays an important part in energy balance. Suppressing appetite by manipulating the diet is a safe way of reducing energy intake and body weight compared to drug therapy and obesity surgery. How various nutrients affect appetite is not fully understood. Non-digestible carbohydrates (NDC) may affect appetite differently due to differences in physio-chemical properties. This project will look into how two different NDC affect appetite and energy intake in overweight individuals in a randomised, double-blinded, placebo controlled parallel study. The NDC under investigation are oligofructose and cellulose, both natural compounds of plant origin. The former is broken down (fermented) in the large bowel by friendly bacteria producing various compounds that may affect appetite and the metabolism of the host. Volunteers will consume one of the two NDC for eight weeks (including a two week run-in period). Appetite study session, functional MRI (fMRI) and MRI body fat scans will be conducted before and after the supplementation with NDC (or during the supplementation in the case of fMRI). Using fMRI the effect of the NDC supplementation on central appetite regulating centres will be investigated. Appetite questionnaires and dietary records will completed under free-living conditions at baseline and during the supplementation to explore the effect on subjective appetite feelings and energy intake, respectively. It is hoped that this project will enhance the understanding of how NDC affect appetite and provide further information on how fermentation of NDC, gut hormone release, body composition, and appetite regulation are linked.

Official Title
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Effect of Oligofructose on Appetite, Gut Hormones and Body Composition in Healthy Overweight Subjects

Conditions
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Appetite Regulation, Obesity

Intervention / Treatment
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* Dietary Supplement: Oligofructose
* Dietary Supplement: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Healthy males and females aged 20-50 BMI 25-35 kg/m2 Weight stable for three months prior to enrollment in study (weight change < 3 kg over a period of three months) Habitual dietary fibre ≤ 25g/day (as assessed by 3-day dietary record) Non-smokers No current or history of endocrine disease, gastrointestinal disease, kidney or liver diseases, cardiovascular disease, pancreatitis, or cancer Hydrogen producers Exclusion Criteria: Use of antibiotic less than three months prior to participation in the study Participation in other research studies in the previous three months Blood donation less than three months before participation in study Anaemia Hypertension Pregnancy or breastfeeding Substance abuse Vegan diet Regular use of prebiotic, probiotic or symbiotic food items/ supplements Intense exercise undertaken for more than 5h per week Metallic or electronic implants e.g. pacemaker, cochlear ear implants, fixed dental braces Claustrophobia Depression

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 50 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: Other
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Oligofructose<br>Participants received 10g of Oligofructose powdered supplements in sachets each containing 10 g dietary fiber) three times per day. Volunteers were instructed to take the supplement with their main meals.The 8-week supplementation period took place between visits 3 and 4 and included a 2-week run-in period to allow the bowel to adapt to the 30 g of dietary fiber. | Dietary Supplement: Oligofructose<br>* Participants will be asked to consume 30g of oligofructose daily for six weeks after a 2-week run-in.<br>|
| Placebo Comparator: Cellulose and maltodextrin<br>Participants received 10g of Cellulose powdered supplements in sachets each containing 10 g dietary fiber) three times per day. Volunteers were instructed to take the supplement with their main meals. Maltodextrin was added to the cellulose supplement. The 8-week supplementation period took place between visits 3 and 4 and included a 2-week run-in period to allow the bowel to adapt to the 30 g of dietary fiber. | Dietary Supplement: Placebo<br>* Participants will be asked to consume 3 doses (a total of 30g dietary fibres) of the placebo product daily for six weeks after a 2-week run-in<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Subjective Appetite Ratings in Hunger Compared to Baseline | Hunger was assessed by visual analogue scales (Each scale is 10cm in length with words anchored at each end, expressing the most positive (Minimum score = 0 cm and means no hunger) and the most negative rating (Maximum score = 10 cm and means very hungry). Compared to baseline after treatment at 56 days | Baseline, 56 days | 
| Subjective Appetite Ratings in Fullness Compared to Baseline | Fullness are assessed by visual analogue scale, 10 cm in length with words anchored at each end, expressing the most positive (feel full: maximum Score=10cm) and the most negative rating (feeling empty: Minimum Score = 0cm), values at baseline and after treatments at 56 days | Baseline, 56 days | 
| Body Weight |  | Baseline, 56 days | 
| Energy Intake | Energy intake was assessed by 7-days food diary at baseline and last week of treatment, diaries were analysed by Dietplan6 software. The values in the table represent the Energy intake as measured over the whole week (as opposed to reporting the Energy intake per day based on the 7 day data). | Baseline, 56 days | 
| Gut Hormone PYY | Total PYY concentrations were quantified using specific and sensitive in-house radio-immunoassays as previously described. | baseline (Day 0) and post-supplementation (Day 56) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Body Composition | Body composition assessed by BMI | Baseline, 56 days | 
| Imaging of Total Adipose Tissue | Total adipose tissue was assessed by FMRI at baseline and after treatment period | Baseline, 56 days | 
| Plasma Short-chain Fatty Acids Concentrations After Treatment | Short-chain fatty acids (acetate, propionate, butyrate) concentrations assessed from plasma at 56 days at 450min timepoint with gas chromatography | Baseline, 56 days | 
| Inflammatory Markers | No data were collected for this Outcome Measure | baseline (Day 0) and post-supplementation (Day 56) | 
| Glycemic Response | Glucose was analyzed in the Department of Clinical Biochemistry, Hammer-smith Hospital, London using an Abbott Architect ci8200 analyzer(Abbott Diagnostics, Maidenhead, UK). | baseline (Day 0) and post-supplementation (Day 56) | 
| Serum Insulin | Plasma insulin concentrations were assayed using RIA kits (Millipore, MO). | baseline (Day 0) and post-supplementation (Day 56) | 
| Breath Hydrogen Levels | breath hydrogen were obtained from volunteers throughout the study session. | baseline (Day 0) and post-supplementation (Day 56) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Appetite regulation, Oligofructose intake