Effect of the Natural Sweeteners Erythritol and Xylitol on Gut Microbiota and Glucose Metabolism in Obese Volunteers

Study Overview
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Brief Summary
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Sugar alcohols such as xylitol and erythritol are increasingly popular as sugar substitutes in the food industry and are also recommended to diabetic patients. Both substances are already in use in the food industry and are freely available. Since the 1970s, beneficial effects on oral health could be demonstrated as oral bacteria were influenced positively. Animal studies showed an increase in gut Clostridium perfringens after xylitol intake; certainly a non-desirable effect. However, studies on effects of erythritol and xylitol on the human gut microbiota are lacking so far. In this trial, investigators aim to examine whether gut microbiota and glucose tolerance can be influenced by polyol intake in a non-diabetic but obese cohort.

Official Title
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Effect of the Natural Sweeteners Erythritol and Xylitol on Gut Microbiota and Glucose Metabolism in Obese Volunteers

Conditions
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Obesity

Intervention / Treatment
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* Dietary Supplement: E967-Xylitol
* Dietary Supplement: E968-Erythritol


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Obese volunteers (BMI > 30kg/m2) Aged 18- max. 55 years Otherwise healthy. Exclusion Criteria: Known cardiovascular disease Diabetes mellitus Arterial Hypertension with medication Dyslipidaemia with medication Known chronic hepatic disease (NASH, hepatitis). Known renal disease: kidney failure Pregnancy Intake of proton pump inhibitors (PPIs) on a regular basis Intake of antibiotics within the last 3 months before inclusion Intake of pro or prebiotics Chronical diseases of the gastrointestinal tract, history of gastrointestinal surgery with major changes to the gastrointestinal tract Substance abuse, alcohol abuse. Inability to follow procedures due to psychological disorders, dementia or insufficient knowledge of project language (German).

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 55 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: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Control<br>20 obese, non-diabetic candidates will serve as control-group. All assessments are carried out just as in the intervention groups. | |
| Active Comparator: E967-Xylitol<br>20 obese, non-diabetic candidates will receive a daily dose of 24g of xylitol. | Dietary Supplement: E967-Xylitol<br> <br> * Other names: Xylitol;|
| Active Comparator: E968-Erythritol<br>20 obese, non-diabetic candidates will receive a daily dose of 36g of erythritol. | Dietary Supplement: E968-Erythritol<br> <br> * Other names: Erythritol;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Glucose tolerance measured with oral glucose tolerance test |  | change from baseline to 8 weeks after polyol intake | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Human gut microbiota composition measured with metagenomic shotgun sequencing |  | change from baseline to 8 weeks after polyol intake | 
| Gut microbial-related metabolites in feces | Metabolomic analysis of the bacterial metabolites present in the feces by combining nuclear magnetic resonance (1H-NMR) and mass spectrometry | change from baseline to 8 weeks after polyol intake | 
| Gastrointestinal tolerance assessed by questionnaire | Gastrointestinal Symptoms Rating Scale (Svedlund et al) | change from baseline to 8 weeks after polyol intake | 
| Gut microbial-related metabolites in urine | Metabolomic analysis of the bacterial metabolites present in the urine by combining nuclear magnetic resonance (1H-NMR) and mass spectrometry | change from baseline to 8 weeks after polyol intake |