PhD defence

The interplay between diet, gastrointestinal complaints and gut microbiota: more than a gut feeling?

PhD candidate ms. I (Iris) Rijnaarts MSc
Co-promotor dr. EG (Erwin) Zoetendal
External copromotor prof. dr. BJM Witteman
dr. ir. NM de Roos
dr. NJW de Wit
Organisation Wageningen University, Human Nutrition & Health

Fri 24 June 2022 16:00 to 17:30

Venue Omnia, building number 105
Hoge Steeg 2
6708 PH Wageningen
+31 (0) 317 - 484500


Irritable Bowel Syndrome (IBS) can greatly impair quality of life. Patients report that symptoms can be induced by specific dietary triggers. We found no differences in dietary triggers between IBS patient subgroups. Furthermore, it has been suggested that IBS patients have alterations in the gut microbiota, but a signature remains elusive. We observed a large variation in gut microbiota composition within subjects over time, therefore caution is needed with conclusions from cross-sectional studies. A high fiber intake has many health benefits, but sustainably increasing fiber intake remains difficult. Personalized dietary advice, provided by a newly developed digital tool, successfully increased fiber intake in healthy and constipated adults with concurrent improvements in gastrointestinal functioning and quality of life in the latter group. To aid fiber intake screening, an 18-item FiberScreen was developed, which successfully detected low fiber intake in ~4 minutes compared to 45-60 minutes by a Food Frequency Questionnaire.