People with irritable bowel syndrome (IBS), a disease of the intestines that results in stomach pain, bloating, gas, diarrhea, and/or constipation, often try a variety of restrictive diets to get relief. The low-FODMAP diet helps approximately 70% of people with IBS live healthy, symptom-free lives.

What is FODMAP?

FODMAP is an acronym for:

• Fermentable

• Oligosaccharides (fructans and galacto-oligosaccharides)

• Disaccharides (lactose)

• Monosaccharides (excess fructose)

• And

• Polyols

In the 1960’s, carbohydrate malabsorption was recognized as a cause for the diarrhea, pain, and bloating associated with IBS. Researchers initially looked at individual sources of carbohydrate, including lactose (the type of carbohydrate in milk), fructose (the type of carbohydrate in fruit), sorbitol (a polyol, or type of lower calorie sweetener), and oligosaccharides (also used as sweeteners). In 2004, the Monash group’s research led them to understand that malabsorption of all of these types of carbohydrates is the cause of IBS symptoms, and they coined the term FODMAP.

Which foods contain FODMAPs?

FODMAPs are found in foods that we enjoy every day:

• Lactose: milk and foods made from milk, including cheese, yogurt, cottage cheese, ice cream, and pudding

• Excess fructose: fruits including apples, cherries, mangos, and pears; vegetables including asparagus and sugar snap peas; sweeteners including agave, high fructose corn syrup, and honey

• Foods high in fermentable oligosaccharides: vegetables including garlic and onions; fruit including bananas, dates, plums and watermelon; grains including wheat, rye and barley; pistachios and cashews; legumes including soybeans, black beans, baked beans, and kidney beans; and chamomile tea, carob, chicory root and inulin (often used as to improve the taste and texture in foods such as yogurt and energy bars)

• Foods high in polyols: vegetables including cauliflower, mushrooms and snow peas; fruit including apricots, blackberries, cherries and watermelon; sweeteners including sorbitol, mannitol, xylitol and isomalt

How does a low-FODMAP diet help people with IBS?

The FODMAP sources of carbohydrates aren’t completely absorbed in people with IBS, leading to the production of gas and changing the motility and function of the intestinal tract. This in turn, leads to symptoms of gas, bloating, diarrhea, or constipation and pain. Over 12 years of research shows that strictly following a low-FODMAP diet for 2-6 weeks and then gradually reintroducing specific foods based on individual tolerance helps approximately 70% of people with IBS reduce or completely eliminate these symptoms. A low-FODMAP diet should not be followed longer than the initial 2-6 weeks because it could reduce the amount of beneficial bacteria in the digestive tract. These bacteria are important for both digestion and overall health. It’s vital to work with a registered dietitian/nutritionist who has specialized training in the low-FODMAP diet to identify the foods that you don’t tolerate correctly, and to make sure that you consume an overall healthful, balanced diet while restricting only the FODMAPs that affect you personally.The Monash University Low-FODMAP Diet smartphone application provides easy access to up-to-date FODMAP composition of foods. It features detailed and ongoing food analysis for a wide variety of food products. The app is available for iPhone, iPad, and Android systems.

By Lynn Grieger, RDN, CDE, CPT, CHWC

References

1. PubMed Health Glossary. Irritable Bowel Syndrome. https://www.ncbi.nlm.nih.gov/pubmedhealth/PMHT0024780/ Accessed 1-8-18Gibson, P. R. (2017) History of the low FODMAP diet. Journal of Gastroenterology and Hepatology, 32: 5–7.

2. Gibson, P. R. (2017) The evidence base for the efficacy of the low FODMAP diet in irritable bowel syndrome: is it ready for prime time as a first-line therapy? Journal of Gastroenterology and Hepatology, 32: 32–35.

3. Hill P, Muir JG, Gibson PR. Controversies and Recent Developments of the Low-FODMAP Diet. Gastroenterology & Hepatology. 2017;13(1):36-45.

4. Monash University. Low FODMAP Diet. https://www.monashfodmap.com/ Accessed 1-9-18