Reliability of a Food Frequency Questionnaire in the Assessment of Dietary Intake Including FODMAPs in Different Populations, and Relationship With IBS Symptoms and the Degree of Self-assessed Physical Activity

During an online assessment participants will fill in questionnaires evaluating demographic data, psychological variables, the degree of self-assessed physical activity and symptoms of irritable bowel. Dietary intake will be assessed by a newly developed food frequency questionnaire (FFQ) and a 4 days food diary. In order to validate the FFQ in different populations, participants will be recruited from university students, staff of UZ Brussel and VUB, and from the community by advertisement (including social media). IBS patients will be recruited from the gastro-enterology outpatient clinic.