inflammatory bowel disease

Nutritional Pearl: Low-FODMAP Diet May Help With IBD

  • ANSWER: Your patients with IBD may find it worthwhile to try a low-FODMAP diet for some relief from symptoms.

    Inflammatory bowel disease (IBD) affects an estimated 600,000 Americans each year, with 2 main types: Ulcerative colitis (UC) and Crohn disease (CD).

    In the past several years researchers have suggested that a diet low in FODMAPs (Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyols) might help patients with these conditions. These are types of carbohydrates that are broken down by bacteria in the large intestine, which use water as part of the process to break down FODMAP molecules into gases that can cause abdominal bloating and pain, among other common symptoms.

    The Research

    A team of researchers in China scoured the literature and performed a meta-analysis of just 6 studies—2 randomized, controlled trials, and 4 before-and-after trials that included just 319 patients with diagnosed IBD. These trials essentially compared the participants' experience of IBD symptoms before adopting a low-FODMAP diet with their experience after adopting a low-FODMAP diet. It's nearly impossible to "blind" people to being on a very specific diet, so it's worth noting that the results should be taken with a grain (or so) of salt.

    The Results

    Those participating in the studies who followed a low-FODMAP diet were almost 25% more likely than those who did not follow a low-FODMAP diet to report that they experienced diarrhea 3 times a day or less. Frequent diarrhea is a common occurrence in those with IBD, regardless of whether they are "in remission" (that is, not actively experiencing other symptoms of IBD) or not.

    On the other hand, those who followed a low-FODMAP diet didn't experience any improvement in their symptoms of constipation. No surprise, to be sure: a diet low in foods containing FODMAPs eliminates many common sources of dietary fiber.

    What’s the “Take-Home”?

    Your patients with IBD may find it worthwhile to try a low-FODMAP diet for some relief from symptoms. Common foods containing FODMAPs include onions, garlic, and cabbage; stone fruits like peaches, nectarines, and plums; legumes (including beans and lentils); dairy products that contain lactose; many sweeteners, including high fructose corn syrup, honey, and agave nectar; and alcohol.

    Safe foods include vegetables such as carrots, bell peppers, lettuce, and tomato; fruits like oranges, grapes, and melons; cheeses that are low in lactose; beef, chicken and eggs, and pork; most nuts; non-dairy milks such as almond milk or coconut milk; and tea or coffee (with non-dairy milk or creamers). Refer your patients to a registered dietitian for detailed dietary assistance with following a low-FODMAP diet.

    Reference:

    Zhan Y, Zhan Y, Dai S. Is a low FODMAP diet beneficial for patients with inflammatory bowel disease? A meta-analysis and systematic review. Clin Nutr. 2018;37:123-129.