Starting the Low-FODMAP Diet

Barbara Bolen, PhD
·6 min read

Following This Diet Can Treat IBS Symptoms

Medically reviewed by Robert Burakoff, MD

Many healthcare providers now routinely recommend the low-FODMAP diet for people with irritable bowel syndrome (IBS). This diet is the first food-based treatment shown to reduce IBS symptoms of gas, bloating, diarrhea and constipation in up to 86% of those who try it.

Up to 70% of people with IBS identify specific foods (milk products, caffeine, peas and beans) that lead to symptoms, but multiple studies demonstrate symptom relief with a low-FODMAP diet.

The diet is a bit tricky and will require a commitment on your part to ensure that you are choosing foods consistent with the diet. Therefore you will not want to take on the diet during a time when you will be extra busy or have limited time in your schedule for food prep and packing.

Find a Trained Professional

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jo unruh/E+/Getty Images

All of the research to date on the diet indicates that the best results are achieved when you get support from a dietitian who is well-versed in the diet. Their expertise is important because:

  • You need to make sure that you are eating a wide variety of foods to get your daily nutritional requirements.

  • It will be helpful to have support as you learn to integrate the diet into your life.

  • They can help you best determine which of the FODMAP types (and in what amounts) are problematic for you.

Start a Food Diary

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Hero Images/Getty Images

As you work through the various diet phases, you will want to keep a food diary. This will help you get a better sense of the relationship between the foods you eat and the symptoms you experience. This step will be beneficial as you work through the various phases of the diet.

A food diary doesn't have to be anything fancy. You just want to keep track of everything you have eaten, what symptoms you are experiencing, and any other factors that might be affecting how you feel, such as stress, your menstrual cycle, etc.

Gather Your Resources

Thomas Northcut/Photodisc/Getty Images
Thomas Northcut/Photodisc/Getty Images

It can be very challenging to remember which foods are low in FODMAPs and which foods are high in FODMAPs and just as challenging to find the right foods to eat. Luckily, the success of the diet has spurred the development of available resources.

The low-FODMAP smartphone app from the researchers at Monash University is a must-have. It can also be helpful to purchase some low-FODMAP cookbooks and frequently visit sites that have low-FODMAP recipes. The more food options you have, the more likely you will be to figure out the most liberal diet you can be on.

Related: Foods to Eat on a Low-FODMAP Diet

Start the Elimination Phase

Morsa Images/DigitalVision/Getty Images
Morsa Images/DigitalVision/Getty Images

To start the diet, you will need to totally eliminate known high FODMAPs foods for a period of two to six weeks. This includes foods from the following FODMAP sub-groups:

  • Fructans: Found in some fruits, grains, nuts, and vegetables (common triggers include onion, garlic, and foods with gluten)

  • Fructose: Found in some fruits

  • GOS: Found in beans, chickpeas, and lentils

  • Lactose: Found in some dairy products

  • Polyols: Found in some fruits, vegetables, and artificial sweeteners

What is left to eat? Plenty of delicious, nutritious things. You can eat anything you want as long as it is low in FODMAPs.

Slowly Reintroduce FODMAPs

Astronaut Images/Caiaimage/Getty Images
Astronaut Images/Caiaimage/Getty Images

After you have hopefully enjoyed a significant decrease in symptoms, it is time to slowly reintroduce some foods back into your diet. For this reintroduction phase, it is recommended that you pick one FODMAP food at a time, to observe the effects.

Your dietary professional can help you to figure out what foods to add. Plan to test each food for three days before adding the next. Start with small amounts of food so as to not cause severe symptoms.

If you experience no symptoms in response to your challenge foods, you can slowly start to increase the quantity you are eating. If you experience symptoms, you can try to test other foods from within the same FODMAP sub-group. If you continue to have a reaction, you should go back to the elimination diet for one week before moving on.

After you have tested all sub-groups and have been relatively symptom-free for some time, you will want to re-test small amounts of the sub-group that you were initially reactive to.

Once you have a good sense of which FODMAP foods you are most reactive to, you can organize your diet so as to eat predominantly low-FODMAP, with minimal consumption of high-FODMAP foods. The goal is to keep your exposure to FODMAPs in a range that does not cause you to experience symptoms.

Keep Testing Your Range of Foods

Gary Burchell/Taxi/Getty Images
Gary Burchell/Taxi/Getty Images

The low-FODMAP diet is not designed to be a "forever" diet. Many foods that are high in FODMAPs are also foods that can be very good for your health.



Takeaway

There are some concerns that FODMAP restriction can have a negative impact on your gut flora. The best thing for both your overall and your digestive health is to eat as wide a variety of healthy foods that you can, focusing on fiber and resistant starches (bananas, oats, rice) known to support healthy digestion.



There is some evidence that once you have followed the low-FODMAP diet you will improve your ability to tolerate previously troublesome foods. Therefore, you will want to be sure to keep re-introducing new foods into your diet at regular intervals to see if your sensitivities have changed.

One helpful way is to set a reminder in your day planner or on your smartphone to go through the reintroduction phase again every three months.

Related: Foods With Resistant Starch That Help With Digestion

Frequently Asked Questions

What is a low FODMAP diet?

The low FODMAP diet eliminates fermentable oligo-, di-, monosaccharides, and polyols—short-chain carbohydrates found in many fruits, vegetables, grains, dairy, legumes, and sweeteners. 

What can you eat on a FODMAP diet?

Foods you can eat on a low FODMAP diet include:

  • Animal-based proteins such as beef, chicken, eggs, and fish

  • Butter

  • Certain cheeses, including brie, camembert, mozzarella, and Parmesan

  • Dairy alternatives, such as almond milk, coconut milk, and hemp milk

  • Firm or extra firm tofu (but not soybeans)

  • Fruits including avocado, banana, blueberry, grapes, cantaloupe, kiwi, lemon, lime, orange, pineapple, raspberry, strawberry, and tangelo

  • Gluten-free grains like amaranth, brown rice, quinoa, and oats

  • Lactose-free dairy

  • Leafy green vegetables

  • Nuts, including almonds, macadamias, pecans, pine nuts, and walnuts

  • Other vegetables, such as bell peppers, carrots, cabbage, eggplant, endive, fennel, green beans, potatoes, squash, tomatoes, and zucchini

  • Sweeteners, including sugar, brown sugar, maple syrup, and artificial sweeteners that do not ent in -ol.

Are potatoes low FODMAP?

Yes, potatoes are a low FODMAP food and can be enjoyed on a low FODMAP diet.

Is broccoli low FODMAP?

Yes, broccoli is a low FODMAP vegetable and can be eaten on a low FODMAP diet.

Why is tofu allowed on low-FODMAP diets when soybeans aren't?

Soybeans are high in the galacto-oligosaccharides (GOS) stachyose and raffinose and can irritate people who are sensitive to FODMAPS. While tofu is made from soybeans, FODMAPs are naturally removed during production along with excess water. Stick to firm and extra firm varieties. Softer tofu varieties may still contain fructans and should be avoided.

Read the original article on Verywell Health.