What is a low-FODMAP diet?

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You may have heard of the low-FODMAP diet as it relates to people with gastrointestinal conditions such as irritable bowel syndrome (IBS). FODMAP stands for fermentable oligosaccharides, disaccharides, monosaccharides and polyols. These are short-chain carbohydrates (ie. sugars) that are poorly absorbed in the small intestine and can cause digestive distress, including symptoms such as cramping, diarrhea, bloating, constipation, and gas.1

High-FODMAP foods include dairy, wheat, beans and lentils, some vegetables such as artichokes, asparagus, onions, and garlic, as well as some fruits such as apples, cherries, pears, and peaches. The idea of the low-FODMAP diet is to eliminate high-FODMAP foods from one’s diet for a period of two to six weeks to allow symptoms to go down and reduce small intestine bacterial overgrowth, if you have it.2 However, some of these foods should be slowly reintroduced to identify which ones trigger symptoms and which ones do not. This allows people to avoid the foods that cause gastrointestinal symptoms while continuing to eat foods that do not. Ideally, this process should be done under the supervision of a medical professional.

The reason that a low-FODMAP diet should be a process of temporarily elimination followed by reintroduction of high-FODMAP foods is because: 1) It would be a highly restrictive diet overwise, and 2) Fermentable carbohydrates feed bacteria in the gut, and eliminating them entirely may have a negative impact on the composition of one’s gut microbiome.2 For example, research does indicate that the elimination of high-FODMAP foods could lead to reduction in Bifidobacterium, which is well-recognized as a health-promoting gut bacteria. More research is necessary to understand the impacts a low-FODMAP diet has on the gut microbiome, but it is broadly accepted that it is effective for alleviating negative symptoms and improving quality of life for people with IBD or IBS. One review indicates that reduced FODMAP intakes do not impact bacterial diversity, but rather total bacterial abundance, and promotes a balanced approach to reduce negative gastrointestinal symptoms while also maintaining a healthy microbiome.3 This is often referred to as a “FODMAP-gentle” approach.

Products marketed and certified as low-FODMAP offer certain consumers peace of mind when they’re shopping for finished products. While they know what FODMAP ingredients they can or cannot eat, checking the labels of all food packaging is profoundly tedious. Certified products allow consumers to more safely shop for finished products while otherwise controlling what high-FODMAP foods they can include in their diet. There are currently two low-FODMAP certifications. One is theMonash University Low FODMAP Certified badge and the other is the FODMAP Friendly logo, both of which also have an app to help consumers find certified products.

People who suffer from IBS may benefit from other interventions besides a low-FODMAP diet alone and should consult a physician before pursuing one, but brands who want to capture a growing base of consumers may benefit from producing and certifying low-FODMAP products. For example, it’s estimated that IBS impacts up to 15% of the U.S. population, and affects women twice as often as men.4 However, because not everyone seeks medical care, up to 75% of cases may go undiagnosed.5 As more consumers seek help for their gastrointestinal symptoms, low-FODMAP foods may offer a measure of relief as well as answers to their digestive health issues.

References

1. FODMAP Diet: What You Need to Know. Johns Hopkins Medicine. https://www.hopkinsmedicine.org/health/wellness-and-prevention/fodmap-diet-what-you-need-to-know (accessed 2024-08-26).
2. Syed, K.; Iswara, K. Low-FODMAP Diet. StatPearls. 2023. https://www.ncbi.nlm.nih.gov/books/NBK562224/ (accessed 2024-08-26).
3. Halmos, E.P.; Gibson, P.R. Controversies and reality of the FODMAP diet for patients with irritable bowel syndrome. J Gastroenterol Hepatol. 2019, 34 (7), 1134-1142. DOI: 10.1111/jgh.14650
4. Irritable Bowel Syndrome (IBS). Johns Hopkins Medicine. https://www.hopkinsmedicine.org/health/conditions-and-diseases/irritable-bowel-syndrome-ibs (accessed 2024-08-26).
5. Ko, E.; Glazier, E. IBS is common, but still may be underdiagnosed. UCLA Health. December 31, 2021. https://www.uclahealth.org/news/article/ibs-is-common-but-still-may-be-underdiagnosed (accessed 2024-08-27).