Small intestinal bacterial overgrowth (SIBO) is a poorly understood condition associated with irritable bowel syndrome (IBS). The current gold standard for SIBO treatment is antibiotics. An effective dietary intervention has not been identified.

To identify patients’ perceptions of how food is related to symptoms and whether specific food intolerances can be related to IBS and a diagnosis of SIBO. We aim to test the hypothesis that high fermentable oligosaccharides, disaccharides, monosaccharides and polyol (FODMAP) foods will provoke symptoms in patients with SIBO.

This is an observational cross-sectional study including patient data collected at baseline from the Canadian Food for IBS (CanaFIBS) study. Participants diagnosed with IBS completed a questionnaire to identify foods which provoked their symptoms. They also completed the IBS symptom severity scoring system (IBS SSS)(0-500 increasing with severity). A glucose breath test was used to assess SIBO status. Students' t tests were used to test statistical significance of continuous variables and chi squared to test categorical variables.

Questionnaires were completed by 91 participants; 65 females aged 40.4 s.d 13.9 years. 12 participants had SIBO. No difference in IBS SSS by SIBO status 272 s.d 104 (non
SIBO) vs 256 sd 97 (SIBO). The two foods most frequently identified by all participants as triggers were wine (72%) and hot spices (64%). High FODMAP fruit, except apples (39%), were infrequently identified as provoking symptoms. Only 17% identified nectarines and pears, 20% apricots, 21% plums and 24% watermelon.

IBS patients self-report both high and low FODMAP foods as provoking their symptoms. This study was unable to determine if there were differences in foods which provoked symptoms by SIBO status.

Dietitians should continue to individually assess IBS patients for trigger food and consider additional strategies to improve digestive health in addition to the low FODMAP diet.