Gut Permeability, Sensitivity and Symptomatology

Inclusion criteria * Age 18 to 70 years * No abdominal surgery (except appendectomy, cholecystectomy, hernia repair, hysterectomy, and C-section). * Written informed consent Exclusion criteria * Females who are pregnant or breastfeeding * Use of tobacco products within the past 6 months (since nicotine may affect intestinal permeability) * Use of NSAIDs or aspirin within the past week (since NSAIDs affect intestinal permeability) * Use of oral corticosteroids within the previous 6 weeks * Ingestion of artificial sweeteners such as Splenda (sucralose), Nutrasweet (aspartame), lactulose or mannitol 2 days before the study tests begins, e.g. foods to be avoided are sugarless gyms or mints and diet soda. * Ingestion of any prescription, over the counter, or herbal medications which can affect gastrointestinal transit 7 days before the study begins. * Proton pump inhibitors. * Antibiotics for the preceding 60 days before the start of the study. * (vii) Alcohol intake beyond the recommended safe limit (\<21 unites per week) * Bleeding disorders or medications that increase risk of bleeding from mucosal biopsies. * Known allergy to fluorescein * Inflammatory bowel diseases, celiac disease.