You have successfully completed the FODMAP elimination phase and feel much better. What happens now? You are ready for the second step: reintroducing FODMAPs. This is an exciting time as you can start learning about the foods that trigger you. After completing this step, you will know a lot about the foods you can bring back into your diet and without getting gut symptoms. Specifically, you will learn which foods you can re-introduce liberally, and which ones you can have in small amounts or only occasionally. In addition, there may be a few ones you will need to avoid for a while (but not forever).
5 Key Things to Know about the Reintroducing FODMAPs
1. There is no set protocol for this phase, only generic guidelines
As soon as your symptoms have considerably improved, you are ready to start reintroducing the high-FODMAP foods that you avoided or limited during the elimination phase. There are different approaches to this phase. An expert dietitian can help you determine the best one for you. The approach can be tailored according to your symptoms, anxiety level, and food preferences.
Researchers are still studying the best way to carry out the FODMAP challenges. Nonetheless, they have identified some key factors that are important to the success of this phase. Let’s take a look at them in detail.
2. Challenge each FODMAP group separately
Over the course of 6-8 weeks you will reintroduce, or better yet, “challenge” all the major FODMAP groups and subgroups one at a time. A challenge involves eating one high-FODMAP food in increasing amounts over the course of 3-4 days. These challenges will allow you to identify which foods may trigger your symptoms. For example, you might challenge blackberries for the sorbitol group. If you don’t have any symptoms while eating the blackberries, this means you will be able to bring back into your diet all the other foods that are high in sorbitol. For example, avocados, stone fruits, and more.
While you are completing this process, it is important to continue eating a low FODMAP diet. The only exception will be the test food you will use for the FODMAP challenge. This allows you to isolate each type of FODMAP and find out which group triggers your symptoms without a doubt.

3. Record your symptoms
When you start reintroducing FODMAPs, it’s key to record the types of symptoms and their severity. A small amount of garlic or honey may not cause any or only mild symptoms. However, bigger portions may cause severe symptoms. Keeping a food and symptom diary will help you track these differences in response to the FODMAP challenges. The Monash FODMAP App can help with this. Keeping a good record of your symptoms (if any) for each challenge will allow you to make informed decisions when you are ready to personalize your diet.
4. Keep re-challenging problem foods
IBS symptoms are known to wax and wane over time. Stress levels and other factors can influence these changes. It is important to keep challenging foods that “failed” you. You may find that at a later time, you are able to better tolerate a FODMAP group you didn’t at first. So, don’t give up. Try your problem foods every 3-6 months and you may be able to keep increasing the variety of your diet. Reducing the dose of the food tested and/or managing stress during the time of the challenges may also increase its tolerance.
5. Don’t do it alone!
When you are ready to reintroduce FODMAPs, it’s ideal to have the guidance of a dietitian who is an expert in this protocol. A dietitian like me can give you the exact foods and schedule of reintroduction (not all high-FODMAP foods are good candidates for the challenges) and help you complete this phase efficiently and correctly. And help you identify the best approach for you, interpret the results of the challenges, and personalize your long-term diet.
In summary, reintroducing FODMAP foods is an essential step for figuring out your IBS triggers. You can start this phase as soon as you feel your symptoms have been reduced with the elimination phase. Although there is not set protocol to complete this step, there are some rules to follow to get accurate results. If you are ready to move on to this exciting part of your journey in managing IBS symptoms, I can help!