Gut Health Enhancement by Eating Favourable Food

Gut Health Enhancement by Eating Favourable Food

Within the GEEF om je buik study the effects of an 8-week intervention with either a diet rich in fiber or fermented food on the gut microbiota will be investigated.

This study is a randomized controlled trial (RCT) with three intervention groups (high dietary fiber group (HDF), high fermented foods group (HFF), and a control group (CG)). The total duration of the study is 5 months and consists of an 8-week intervention (2-week ramp up period with dietary guidelines, followed by 6-week period with dietary guidelines + additional consumption of study products) and a follow-up after 3 months. In total 147 subjects will be included.

Inclusion Criteria:

• Men and Women, aged ≥18 - ≤70 years;
• Being able to read and speak Dutch;
• Willing to keep a stable dietary pattern throughout the study, apart from the dietary advice in the study;
• Having a smartphone compatible with the Lifedata or PocketQ app to fill out the daily questionnaires.

Exclusion Criteria:

• Having a disease or medical condition which can influence the study results such as diabetes, cancer, diagnosed irritable bowel syndrome, renal disease, liver enzyme abnormality, malignant neoplasm, or a history of inflammatory diseases (such as multiple sclerosis, rheumatoid arthritis, and inflammatory bowel disease);
• Having a history of intestinal surgery that might interfere with study outcomes (this does not include an appendectomy or cholecystectomy);
• Average dietary fiber intake of ≥18 gram (women) or ≥22 gram (men) per day, according to the fiber screen questionnaire (see F1 questionnaires);
• More than 3 servings of fermented foods per day as assessed with the fermented food frequency questionnaire (see F1 questionnaires);
• Having a Body Mass Index (BMI) of ≥ 30 kg/m2 (self-reported);
• Currently following a strict diet and unwilling or unable to change; for example, a gluten free diet or a "crash diet" using meal substitutes;
• Specific food allergies that interfere with dietary intervention (for example, gluten, lactose, etc);
• Use of prebiotics, probiotics and/or synbiotics (this should be stopped 4 weeks before the start of the study) and use of fiber supplements;
• Use of antibiotic treatment less than 3 months before start of the study and/or use of antibiotics during the study;
• Use of medication that can interfere with the study outcomes, as judged by the medical supervisor;
• Alcoholic use of ≥14 (women) or ≥28 (men) glasses of alcoholic beverages per week;
• Use of soft or hard drugs (should be stopped at least 4 weeks before start of the study);
• Being pregnant or lactating;
• Participation in another clinical trial at the same time;
• Student or employee working at either Food, Health and Consumer Research from Wageningen Food and Biobased Research, Microbiology at VU, the MLDS, at WholeFiber, Keep Food Simple or at Cidrani;
• Unable to follow or comply to study rules.