A Study of Perturbation of Human Small Intestinal Colonic Permeability

Inclusion Criteria: * Healthy, non-obese, non-pregnant volunteers. * 1:1 Male/Female Ratio. * BMI \< 30 kg/m\^2. Exclusion Criteria: * Diabetes. * Uncontrolled hypertension (with BP measured \> 140/90mmHg in the CRTU) * BMI ≥ 30 kg/m\^2. * Chronic NSAID use (\> 1 day/week). * Use of oral antibiotics for 2 weeks prior to and during the entire 5 day study period. * Known intolerance of castor oil. * Diagnosis of gastrointestinal diseases that are associated with abnormal intestinal or colonic permeability such as inflammatory bowel diseases, irritable bowel syndrome and celiac disease. * Prior intestinal or colonic resection. * Participation in highly vigorous exercise such as running \> 5 miles per day in week prior to the permeability test.