Low FODMAP Diet: A Guide to Understanding the Basics and Getting Started

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Written By Berry Mathew

The low FODMAP diet is becoming more popular day by day – I’m sure you’ve heard of it on the internet or from a friend. When people talk about a “FODMAP diet”, they are usually talking about a diet that has a low amount of sugars and causes intestinal distress in some people. Dietitians created the FODMAP diet for people with Small Intestinal Bacterial Overgrowth (SIBO), or Irritable Bowel Syndrome (IBS). The main reason was to help people with such problems assess which foods cause symptoms and which ones reduce them.

According to Hazel Galon Veloso, a gastroenterologist from Johns Hopkins, the low FODMAP diet plan is very restrictive; however, it is only temporary. The goal of this diet is to eliminate specific foods from your daily meals.  Therefore, it is essential to consult with your doctor before starting this diet plan. 

This article helps you to understand all the basic things about the FODMAP diet. Before getting started, Let’s first cover the meaning of the FODMAP diet, how it works, and who should try it.

Let’s dive in!

What Are FODMAPs?

FODMAP is an acronym for fermentable oligosaccharides, disaccharides, monosaccharides, and polyols. These are typically carbohydrates that are not adequately absorbed by the intestine, leading to water retention in the digestive tract. Moreover, the useful bacteria in the gut often ferment these carbs because they cannot be digested. As a result, they cause a lot of gas to be produced in the intestines.

For this reason, FODMAPs are well-known for causing discomforts such as gas, bloating, and stomach pains. Furthermore, these foods cause constipation and in some cases, even diarrhea. In fact, up to 60% of people with IBS claim that foods that are high in FODMAPS always make their symptoms worse.

FODMAPs can be found in a wide range of foods but in differing amounts. There are foods that have many while others only have one or two. I have compiled the list below to show you all the food sources that are part of the FODMAP group.

  • Oligosaccharides are foods such as rye wheat, nuts, legumes, garlic, and onion.
  • Disaccharides are all products that contain lactose. They include milk, yogurt, soft cheese, ice cream, buttermilk, condensed milk, and whipped cream.
  • Monosaccharides are all foods that contain fructose. They include fruits like apples, watermelons, pears, and mango. Sweeteners such as honey, agave nectar, and high fructose corn syrup are also a part of this group.
  • Polyols include foods such as apples, pears, cauliflower, mushrooms, stone fruits, and snow peas. Low-calorie sweeteners, such as those in sugar-free gum and mints are also a part of this group.

What Foods Are Included in a Low Fodmap Diet Plan?

Typically, the average daily meals contain around 15 to 30 grams of carbohydrates. Therefore, a low FODMAP meal aims to reduce the intake of carbs to about 0.5 grams per day. And the only way to ensure that you remove all unnecessary carbs is by following the recommendation of eating small, frequent meals. If you find it a bit challenging to know what to eat and what to avoid, opt for a low FODMAP food delivery from a certified service.

Luckily, there are many foods that naturally contain low amounts of FODMAPs. Therefore, they are safe to eat when you are following an IBS meal plan.

  • Proteins such as beef, eggs, chicken, fish, lamb, pork, prawns, and tofu.
  • Whole grains and starches like lentils, white and brown rice, corn, quinoa, oats, cassava, and potatoes.
  • Vegetables include bean sprouts, cucumber, zucchini, carrots, eggplant, bell peppers, carrots, and radishes.
  • Fruits such as pineapple, blueberries, cantaloupe, raspberries, strawberries, honeydew melon, kiwi, limes, starfruit, guava, and grapes.
  • Nuts like macadamia nuts, pecans, peanuts, walnuts, pine nuts, and almonds (no more than 10 per sitting). 
  • Condiments like salt, wasabi powder, white rice vinegar, cumin, saffron, cinnamon, coriander, cardamom, paprika, soy sauce, fish sauce, mustard, and pepper.
  • Seeds from pumpkins, sunflowers, sesame as well as linseed.
  • Dairy including Greek yogurt, lactose-free milk, Colby, Parmesan, cheddar, and mozzarella cheeses.
  • Oils including olive and coconut oils.
  • Beverages like water and peppermint tea.


Even though coffee, black and green teas are low FODMAP foods, it is not recommended to include them in your IBS meals. The caffeine in these drinks often causes the symptoms of people with IBS to get worse.

In addition, always look for added FODMAPs on the ingredient lists of all your packed foods because some manufacturers add them as fat substitutes, prebiotics, or even low-calorie sugar substitutes. 

Who Can Eat a Low FODMAP Meal?

You can only eat low FODMAP foods if you’re diagnosed with IBS or SIBO. If you’re healthy, this diet will do more harm than good. Here’s why.

Most FODMAPs are prebiotics, meaning that they provide a good environment for the growth of useful bacteria in the gut. For this reason, removing them from your diet will harm the useful bacteria in your intestines and affect your overall health.

Moreover, removing fruits and vegetables from your daily meals often leads to severe deficiencies in important minerals and vitamins. Removing the fruits will also reduce the amount of fiber you eat and worsen constipation problems. For that reason, you should only follow the FODMAP diet under the guidance of a medical doctor with expertise in digestive disorders. This way, you’re assured that your daily diet has enough nutrients,  and you’ll avoid potential imbalances.

How to Follow a Low FODMAP Diet Plan

The low FODMAP diet is a little complex and involves the following three stages.

Stage 1: Restriction

The first step when starting a FODMAP diet is to avoid all high FODMAP foods. Most people who follow this diet assume that they should avoid FODMAPS forever, but they are wrong. You should only restrict yourself for about 4 to 8 weeks because FODMAPs are crucial to digestive health.

So, how will you know when to move to the second stage?

Once you feel enough relief from your symptoms, you’ll be ready to progress to the next stage. Most people who try this diet report that their symptoms fade in about 6 to 8 weeks. However, there are a few lucky people who notice improvements within a week of starting the diet.

Stage 2: Re-Introduction

Once your symptoms have subsided or reduced, you can begin reintroducing high FODMAP foods into your diet. This step will help you to:

  • Identify which FODMAPs you can tolerate
  • Establish the quantity of FODMAPS you can tolerate.

At this stage, you still remain on a low FODMAP diet while testing one high FODMAP food every three days. This way, you will avoid crossover or additive effects. It is best to go through this stage with the guidance of a registered dietitian.

Stage 3: Personalization

This last stage is also known as the “modified low FODMAP diet” because you only bring the FODMAPs that you can tolerate well back into your diet. 

Final Thoughts

The main reason for following a low FODMAP diet is to identify foods that irritate the gut and then remove them completely from your diet. If you have conditions such as Irritable Bowel Syndrome (IBS) or Small Intestinal Bacterial Overgrowth (SIBO), you will definitely benefit from this diet.

Even though you’re required to follow a FODMAP diet like clockwork, it is only for a short period. Therefore, as soon as you identify which foods cause you problems and eliminate them, you will be able to live a healthy life enjoying the foods you love.