The study aims to determine the effect of gum arabic on gut bacteria and GI function.

To compare the effect of placebo, low-dose prebiotic, or high-dose prebiotic on gut microbiota composition and function, GI transit and permeability, and assess development of symptoms or a change in pre-existing symptoms present, in patients with recent history of clinically diagnosed diverticulitis which has been successfully treated.

Inclusion Criteria:

1. Recent diagnosis of diverticulitis (within 24 months) and at least 4 weeks post antibiotic use
2. Age 18-80

Exclusion Criteria:

1. Prior history of gastrointestinal surgeries (except appendectomy and cholecystectomy)
2. Known diagnosis of inflammatory bowel disease (Crohn's or ulcerative colitis), microscopic colitis, celiac disease, or other inflammatory condition other than diverticulitis
3. Use of tobacco products within the past 6 months (since nicotine may affect intestinal permeability)
4. Use of NSAIDs or aspirin within the week prior to Visit 2 and Visit 5 (permeability and transit testing visit since NSAIDs affect intestinal permeability)
5. Use of osmotic laxatives one week prior to Visit 2 and for the duration of the study
6. Use of oral corticosteroids within the previous 6 weeks and for the duration of the study
7. Ingestion of artificial sweeteners such as Splenda™ (sucralose), Nutrasweet™ (aspartame), sorbitol, xylitol, lactulose, or mannitol 2 days before and during the permeability testing days, e.g. foods to be avoided are sugarless gums or mints and diet beverages
8. Antibiotic use within 4 weeks of completion of the initial stool kit and/or Visit 2 testing appointment and for the remainder of the study (they can complete the stool kit and Visit 2 after a 4-week washout period)
9. Bowel preparation for colonoscopy less than one week prior to the completion of the first stool kit and Visit 2 and during the remainder of the study
10. Pregnancy or plan to become pregnant within the study timeframe
11. Vulnerable adults
12. Egg allergy or resistant to ingesting eggs
13. Diagnosis of diabetes
14. Any other disease(s), condition(s) or habit(s) that would interfere with completion of study, or in the judgment of the investigator would potentially interfere with compliance to this study or would adversely affect study outcomes