Studies suggest that in one quarter of patients, symptoms of irritable bowel syndrome (IBS) may be caused or exacerbated by diet.

Researchers from the University of North Carolina School of Medicine, at Chapel Hill, reviewed the data from a clinician’s perspective.

First, the details.

  • A narrative review — a summary of studies evaluated from the reviewers’ experience — was conducted.

And, the results.

  • Despite a long history of enthusiastic use, fiber is marginally beneficial.
    • Insoluble fiber may worsen symptoms.
    • Some patients with IBS, especially those with constipation, will improve with increased intake of soluble fiber.
    • Prebiotic fibers have not been adequately tested.
  • Daily use of peppermint oil is effective in relieving IBS symptoms.
  • The usefulness of probiotics in the form of foods such as live-culture yogurt and buttermilk for IBS symptoms is not established.

The bottom line?
The authors concluded, “In clinical practice, it is very difficult to establish that a patient’s symptoms result from an adverse reaction to food.”

“A modified exclusion diet and stepwise reintroduction of foods or trials of eliminating classes of food may be useful.”

6/30/09 19:45 JR

Hi, I’m JR

John Russo, Jr., PharmD, is president of The MedCom Resource, Inc. Previously, he was senior vice president of medical communications at, a complementary and alternative medicine website.