Fermentable carbohydrate and gut hormone release

INTERVENTION: This is a randomised crossover study during which healthy volunteers are clinical research facility inpatients for four days on three separate occasions. On day one of the study, a naso‐enteric tube is inserted through the nose, with a small balloon at the terminal end which is inflated and used to carry the tube through the small intestine by peristalsis. Once the tube reaches the terminal ileum, the balloon is deflated and the tube is restrained from additional movement for the rest of the 4‐day study visit. During the three separate study visits, volunteers will be provided with different diets differing in carbohydrate quality. All the diets have similar macronutrient content (55% energy from carbohydrate, 30% energy from fat, 15% energy from protein). In a randomised order, volunteers receive: 1. DIET 1: Highly refined and processed carbohydrate: Foods will be low in fibre and intact cell structures. 2. DIET 2: High fibre with high intake cellular structure: Will contain foods with resistant cell structures such as beans, nuts, minimally processed wholegrain wheat cereal and vegetables. 3. DIET 3: High fibre with disrupted cellular structure: The same as DIET 2, but the food is processed in order to disrupt the cell structure. Volunteers are fed one of the diets over the 4‐day study period. The diet starts on Day 1 and end on Day 4. The collection of ileal samples start on day 3. On day 4, ileal samples are collected as on day 3 and are matched with blood sampling and visual analogue scales (VAS) to assess appetite responses. Volunteers will also be asked to collect a stool sample on each day of the 4‐day study period. CONDITION: Specialty: Metabolic and endocrine disorders, Primary sub‐specialty: Metabolic and endocrine disorders; UKCRC code/ Disease: Cancer/ Malignant neoplasms of digestive organs, Metabolic and Endocrine/ Obesity and other hyperalimentation, Stroke/ Cerebrovascular diseases, Oral and Gastrointestinal/ Other diseases of the digestive system, Cardiovascular/ Pulmonary heart disease and diseases of pulmonary circulation ; Digestive System PRIMARY OUTCOME: 1. Metabolic profiling of ileal samples is measured using 1H NMR spectroscopy, ultra‐performance LC‐MS and GC‐MS on Day 3 and Day 4 at baseline and 60, 120, 180, 240, 300, 360, 420 and 480 min following breakfast; 2. Microbiological profiling of ileal samples is measured using 16S sequencing on Day 3 and Day 4 at baseline and 60, 120, 180, 240, 300, 360, 420 and 480 min following breakfast INCLUSION CRITERIA: 1. Male or female 2. Age between 18‐65 years (inclusive) 3. Body mass index (BMI) of 18‐30 kg/m2 4. Willingness and ability to give written informed consent and willingness and ability to understand, to participate and to comply with the study requirements SECONDARY OUTCOME: Current secondary outcome measures as of 13/09/2018:; 1. Metabolic and hormonal profiling of blood samples is measured using radioimmunoassay, 1H NMR spectroscopy, ultra‐performance LC‐MS and GC‐MS on Day 4 at baseline and 60, 120, 180, 240, 300, 360, 420 and 480 min following breakfast; 2. Microbiological profiling of faecal samples is measured using 16S sequencing on each day of the 4‐day study visit; 3. Subjective appetite is measured using visual analogue scales on Day 4 at baseline and 60, 120, 180, 240, 300, 360, 420 and 480 min following breakfast; 4. Nausea is measured using visual analogue scales on Day 4 at baseline and 60, 120, 180, 240, 300, 360, 420 and 480 min following breakfast; 5. Metabolic profiling of faecal samples is measured using 1H NMR spectroscopy on each day of the intervention; 6. Detection of plant structures, cell structures and starch granules in ileal samples is measured by microscopy on Day 3 and Day 4 of the intervention; ; Previous secondary outcome measures:; 1. Metabolic and hormonal profiling of blood samples is measured using radioimmunoassay, 1H NMR spectroscopy, ultra‐performance LC‐MS and GC‐MS on Day 4 at baseline and 60, 120, 180, 240, 300, 360, 420 and 480 min following breakfast; 2. Microbiological profiling of faecal samples is measured using 16S sequencing on each day of the 4‐day study visit; 3. Subjective appetite is measured using visual analogue scales on Day 4 at baseline and 60, 120, 180, 240, 300, 360, 420 and 480 min following breakfast; 4. Nausea is measured using visual analogue scales on Day 4 at baseline and 60, 120, 180, 240, 300, 360, 420 and 480 min following breakfast