Low-FODMAP Diet

Photo Credit: Rimma Bondarenko/Shutterstock
Photo Credit: Rimma Bondarenko/Shutterstock 

The Low-FODMAP Diet is a temporary dietary plan that limits the intake of certain types of fermentable carbohydrates, including oligosaccharides, disaccharides, monosaccharides, and polyols. It is used to treat symptoms of Irritable Bowel Syndrome (IBS). As some patients with IBD also have the coexistence of IBS, it may be helpful to treat persistent gastrointestinal (GI) symptoms in patients with IBD who have low levels of inflammation, where symptoms may be attributed to IBS rather than IBD.

In following the Low-FODMAP Diet, specific carbohydrates (high-FODMAP foods) are excluded for a period of time and then slowly reintroduced in order to determine which ones in particular may activate symptoms. Small daily amounts of each carbohydrate type are generally well tolerated. The cumulative effect of consuming large daily amounts of higher FODMAP carbohydrate foods may be the cause of GI distress. Higher FODMAP fruits and vegetables that are excluded include onions, garlic, apples, etc; it is recommended to specifically include fruits and vegetables that are low in FODMAPs, such as berries, nuts, carrots, green leafy vegetables, etc. See charts below.

Patients with IBD seeking to implement a Low-FODMAP Diet should consult with a dietary professional as it can be difficult to implement properly. Excessive fiber intake from fruits and vegetables can cause GI pain and increased risk of a bowel obstruction, particularly in patients with strictures. Fiber-containing foods should be added in small quantities at a time to allow the body to adapt to processing more fiber and build the proper muscles and bacteria to handle fiber. Patients with strictures should take extra care to first peel fruits and vegetables and cook them well and may need to consider pureeing them initially.

For patients who are not currently consuming many fiber-containing foods, slowly adding in high-FODMAP foods could cause gastrointestinal symptoms due to the fiber rather than the carbohydrates. High-FODMAP foods draw water into the intestines, which can perpetuate diarrhea. The fermentation of high-FODMAP foods by bacteria in the colon can cause bloating, gas, and cramping pain.

As the low-FODMAP diet has not been shown to reduce inflammation, it is recommended for symptom relief only, rather than disease management. It is further recommended for use short term (4 weeks) rather than longer term because it may adversely affect the microbiome (Cox SR et al).

Low-FODMAP Foods (Allowed)

  • Eggplant, green beans, bok choy, bell pepper, carrot, cucumber, lettuce, potato, tomato, zucchini
  • Cantaloupe, grapes, kiwi, orange, pineapple, strawberries
  • Almond milk, brie and camembert cheese, feta cheese, hard cheeses, lactose-free milk, soy milk (made from soy protein)
  • Eggs, firm tofu, plain cooked meats/poultry/seafood, tempeh
  • Corn flakes, oats, quinoa flakes, quinoa/rice/corn pasta, rice cakes (plain), sourdough spelt bread, wheat-/rye-/barley-free breads
  • Dark chocolate, maple syrup, rice malt syrup, table sugar
  • Macadamias, peanuts, pumpkin seeds, walnuts

Source: Monash University

High-FODMAP Foods (Restricted)

  • Apples, pears, mangoes, cherries, figs, nashi pears, pears, watermelon, dried fruit (high in fructose)
  • Artichoke, garlic, leek, onion, spring onions (high in fructans)
  • Mushrooms, cauliflower, snow peas (high in mannitol)
  • Wholemeal bread, rye bread, muesli containing wheat, wheat pasta, rye crispbread (Fructans and GOS)
  • Red kidney beans, split peas, falafels, baked beans (high in GOS)
  • Soft cheeses, milk, yogurt (high in lactose)
  • Cashews and pistachios (high in GOS and fructans)
  • Honey, HFCS, artificial sweeteners (high in polyols)

Source: Monash University


Nutritional Therapy for IBD

Improving the Care of Patients with Crohn’s Disease and Ulcerative Colitis through Nutrition