A Beginner’s Guide to the FODMAP Diet

Digestive issues are fairly common and include everything from Gastroesophageal Reflux Disease (GERD), Celiac Disease, Ulcerative Colitis, and Irritable Bowel Syndrome (IBS). While many of these conditions are commonly triggered by the foods we eat, the only way you can determine whether or not certain foods are playing a factor is through process of elimination — also known as an elimination diet.

One of the most common elimination diets that doctors will recommend to patients is known as the FODMAP diet, which stands for fermentable oligo-, di-, mon-saccharides and polyols — the scientific terms that are used to classify common and problematic carbohydrates that trigger symptoms such as gas, bloating, and stomach/abdominal pain. There are 4 groups of FODMAP’s: Oligosaccharides, disaccharides, monosaccharides, and polyols, and they all come with different dietary sources.


  • Garlic
  • Onions
  • Artichokes
  • Legumes
  • Lentils
  • Chickpeas
  • Wheat
  • Rye


  • Milk
  • Milk powder
  • Yogurt
  • Ice cream
  • Cheese


  • Apples
  • Pears
  • Watermelon
  • Figs
  • Mangoes
  • Honey
  • Agave


  • Blackberries
  • Cherries
  • Nectarines
  • Prunes
  • Lychee
  • Mushrooms
  • Certain low-calorie sweeteners

You can find more in-dept information on these high-FODMAP foods here. As for some examples of low FODMAP food alternatives, you can eat things like lettuce, tomato, zucchini, cantaloupe, grapes, mandarin, strawberries, pineapple, kiwi, feta cheese, eggs, poultry, quinoa, peanuts, pumpkin seeds, walnuts, and lactose-free or soy milk.

The digestive system can benefit from following a low-FODMAP diet in a number of ways. If you suffer from IBS, for example, you may notice a significant decrease in symptoms such as stomach pain and bloating, in addition to managing and reducing other digestive symptoms such as diarrhea and/or constipation, and flatulence. Once these symptoms are reduced, your quality of life can also improve significantly. Some individuals who’ve followed a low-FODMAP diet even say that their energy levels have increased, though more research needs to be done on this.

Following the FODMAP diet is more complex than one might realize, however, as it’s not simply about eliminating foods. Instead, it involves three different stages: Restriction, Reintroduction, and Personalization.

Stage 1 — Restriction: This stage requires strict restriction of all high-FODMAP foods for approximately 3 to 8 weeks, as this is how long it may take for your symptoms to improve. Once you notice an improvement in your symptoms, you can proceed to the next stage.

Stage 2 — Reintroduction: Following the restriction stage, you can start to reintroduce the foods you initially eliminated back into your diet. However, it’s important that you not reintroduce each food all at once. Instead, you need to be systematic about it and test certain foods one by one for at least three days at a time. This will help you to determine which FODMAPS you can tolerate and how many, and which you are sensitive to.

Stage 3 — Personalization: The last of the stages, this is based on both your tolerance and intolerance of certain FODMAP foods discovered through the second stage. Essentially, it’s like creating a personalized diet plan designed for you and you only.

In many cases, a FODMAP diet is often recommended when other avenues have been exhausted. At the same time, like any diet, the FODMAP diet also takes determination, as it is an intensive process in both time and resources and can be easy to fail at if you’re not prepared. Always talk to your physician about any questions you have when it comes to this or other aspects of your diet. You can even benefit from the help of a dietitian. By being better prepared, the higher the likelihood that your FODMAP diet will be successful. If your symptoms don’t improve or worsen, then you should address this with your physician as well as more investigating (such a tests, etc.) may need to be done to determine if there are any other underlying causes contributing to your symptoms.

Originally published at alighahary.ca on January 28, 2019.



Dr. Ali Ghahary is a Family Physician in Vancouver, British Columbia, Canada. http://www.alighahary.ca

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