Fermentable Oligo-, di-, monosaccharides, and polyols (FODMAP): A diet restricting food containing FODMAP—such as wheat, onions, beans, many fruits, and sorbitol—may be “worth trying” in patients with IBD who have irritable bowel symptoms, such as bloating or watery diarrhea, despite appropriate treatments for underlying active IBD or bile salt malabsorption.

Evidence From Epidemiological Studies

Epidemiological studies suggest a “strong association” between CD and a high pre-illness intake of refined sugar, meat, and animal fat, and low fiber intake. However a low-sugar, high-fiber diet has not been demonstrated beneficial. 

In UC cases, a strong correlation was found between high pre-illness consumption of meat, with no reports of UC occurring in vegetarians.

Dietary Guidance

The authors offer “reasonable dietary advice” for patients with IBD.

Patients with CD are advised to:

  • Reduce consumption of animal fat (ie, approximately 90g of fat—or 30 percent of energy requirements—in a person who has an intake of 2500 kcal/day).
  • Avoid foods that are high in insoluble fiber (eg, stringy or fibrous vegetables such as green beans, corn on the cob, tomato skins, orange pith, potato skins, and wheat bran).
  • Avoid processed fatty foods (often high in fat and usually containing emulsifiers). Also avoid exposure to dishwashing detergents by thorough rinsing, as the detergents also contain emulsifiers.
  • Supplement with vitamin D—up to 1200 IU/day.
  • Dairy products, if tolerated, can be consumed to help ensure adequate calcium intake.

Patients with UC are advised to:

  • Minimize consumption of meat (no more than once/week), particularly red and processed meats.
  • Avoid margarine, and use olive oil, since there is “weak evidence” that olive oil might be protective.
  • It is not necessary to exclude dairy products and/or lactose, since strict exclusion of these foods is not supported by current evidence.


The authors conclude that there is a “clear need” for high-quality interventional studies of “dietary manipulation” in IBD treatment.


1. Centers for Disease Control and Prevention. Inflammatory bowel disease (IBD). (2011) Available at: www.cdc.gov/ibd/. Accessed: September 24, 2013.

2. Loftus EV Jr. Clinical epidemiology of inflammatory bowel disease: Incidence, prevalence, and environmental influences. Gastroenterology. 2004;126(6):1504-1157.

3. Richman D, Rhodes JM. Review article: evidence-based dietary advice for patients with inflammatory bowel disease. Aliment Pharmacol Ther. Published Online: September 17, 2013.