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What Is the Low-FODMAP Diet?

Published: August 10, 2020

Reviewed: April 27, 2023

Woman with open refrigerator - What Is the Low FODMAP Diet?
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Like any eating style that makes the news, the low-FODMAP diet has generated quite a buzz. This eating plan was originally developed to help manage the symptoms associated with irritable bowel syndrome. But wait, what exactly is a low-FODMAP diet? And should you be following it?

What Does FODMAP Mean?

FODMAP is an acronym for:

Fermentable

Oligosaccharides

Disaccharides

Monosaccharides

and

Polyols

These short-chain carbohydrates are found naturally in many of the foods we eat. These particular types of carbohydrates share three important characteristics: They may be poorly absorbed in the intestine, draw extra water into the intestine and are rapidly fermented by bacteria in the gut. Depending on the quantity consumed and a person's tolerance, FODMAPs may lead to increased gassiness, bloating, abdominal pain and diarrhea for those with sensitivities to them. FODMAPs are not inherently bad and are found in a variety of very nutritious foods.

Consult a medical professional to rule out celiac disease, cancer and food allergies or intolerances prior to starting any new diet — especially if you're experiencing stomach pain or intestinal problems. If a FODMAP diet is prescribed, working with a registered dietitian nutritionist is important to make sure you're getting the nutrients you need.

Four Types of FODMAPs

  • Oligosaccharides

There are two different groups of oligosaccharides: fructans and galactans. Fructans are found in wheat products, onions, garlic, artichokes and inulin. Galactans are found in lentils, chickpeas, broccoli, beans, Brussels sprouts and soy-based products.

  • Disaccharides

The most commonly known disaccharide is lactose, which naturally occurs in milk and some dairy products and requires lactase, a digestive enzyme, for absorption. Milk, yogurt, soft cheeses, ice cream and puddings are all disaccharides containing lactose.

  • Monosaccharides

Fructose is a monosaccharide found in fruits. Fructose absorption is enhanced when it is combined with sources of glucose, another type of sugar. Therefore, when it comes to FODMAPs, not all fruits are equal. Those containing equal amounts of fructose and glucose may be more easily tolerated. Some examples of higher-fructose containing foods that may cause gastrointestinal symptoms include (but are not limited to) agave, honey, mangos, watermelon, sugar snap peas and high fructose corn syrup.

  • Polyols

Polyols are sugar alcohols found in some stone fruits (such as cherries and nectarines), apples and pears; in vegetables such as mushrooms and cauliflower; and in some sugar substitutes containing xylitol or sorbitol.

How the Low-FODMAP Diet May Work

This diet starts with a low-FODMAP period, usually ranging from six to eight weeks. Then, under a medical professional's observation, a patient will gradually reintroduce certain FODMAP-containing foods. During the reintroduction period, it is vital to keep track of signs and symptoms of gastrointestinal distress in order to help identify food offenders.

Reintroduction is important because over-restriction can cause harm too. Cutting too many fruits, vegetables, plant-based proteins and dairy foods from the diet can lead to increased risk of deficiencies in nutrients such as fiber, minerals such as calcium, protein (for vegetarians or vegans) and vitamins A, C and D. A registered dietitian nutritionist can help manage the reintroduction phase by developing an eating plan that meets a person's nutrient needs. Remember, this is a low-FODMAP diet, not a no FODMAP diet; it is a highly individualized therapy that was designed to help manage symptoms, not to cure them completely.

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