Effect of Rate Of Delivery on Colonic Fermentation of inuliN (EON)

To test whether slowing the rate of delivery of inulin with either psyllium or divided dosing of inulin, will reduce colonic gas production as compared to inulin combined with placebo.To obtain pilot data on link between habitual diet and fermentation of inulin.

Inclusion Criteria:Aged 18 or older.Able to give informed consent.Scoring ≤3 (i.e., mild, or less) for symptoms of flatulence, bloating and abdominal pain in previous 2 weeks using a modified Gastrointestinal Symptom Rating Scale (5).Agrees to consume the meals provided.Agrees to not smoke during the breath hydrogen sampling periodExclusion Criteria:Pregnancy declared by candidate.History declared by the candidate of pre-existing gastrointestinal disorder that may affect bowel function.Reported history of previous resection of the oesophagus, stomach, or intestine (excluding appendix).Intestinal stoma.Any medical condition potentially compromising participation in the study e.g., type 1 diabetes mellitus, respiratory disease limiting ability to use breath hydrogen analyser, known intolerance to one of the test substances.Will not agree to dietary restrictions required nor consume the standard meals required during the study day.Unable to stop drugs known to alter GI motility including mebeverine, opiates, monoamine oxidase inhibitors, phenothiazines, benzodiazepines, calcium channel antagonists for the duration of the study (Selective serotonin reuptake inhibitors, low dose tricyclic antidepressants, antihistamines, and oral contraceptive pill will be recorded in the CRF but will not be an exclusion criteria).Participants who are taking antibiotics or probiotics as they might alter gut microbiota.Poor understanding of English language.Participation in night shift work the week prior to the study day. Night work is defined as working between midnight and 6.00 AM.Anyone who in the opinion of the investigator is unlikely to be able to comply with the protocol e.g., cognitive dysfunction, chaotic lifestyle related to substance abuse.Having taken part in a research study in the last 3 months involving invasive procedures or an inconvenience allowance.