The Mini Guide to FODMAP Challenges and Reintroducing FODMAPs

First things first: Remember there are Three Phases to the low FODMAP diet!


  1. The first phase is the ‘low FODMAP restriction diet’ – which should be followed for approximately 4 weeks, up to about 8-12 weeks maximum.

  2. After this you enter phase two the ‘reintroduction phase’ which itself is split into ‘re-challenging FODMAPs’ which tends to take 6-10 weeks and ‘reintroducing FODMAPs’ which is an ongoing process.

  3. The third and final phase is being termed the ‘maintenance phase‘. Once you have reintroduced tolerated FODMAPs back into the diet most people follow an adapted intake of high FODMAP foods.  This often leads to consumption of a modified FODMAP diet, which is a self-management process and diet to help maintain control of functional gut symptoms.

Most importantly when considering a low FODMAP diet (all three phases) ensure you have seen a medical professional to diagnose your gut symptoms. If you are not sure what investigations should have been completed for correct diagnoses read this article. Ideally the low FODMAP diet treatment should be completed under the supervision of a trained FODMAP dietitian and tailored to the individual.

Re-challenging FODMAPs


The aim of re-challenging is to understand what individual FODMAPs trigger symptoms and at what portion sizes these individual FODMAPs trigger symptoms.


When re-challenging FODMAPs there are protocols and guidelines to follow which will help guide you through the process in a systematic way to ensure the results obtained are as accurate as possible. An example protocol for re-challenging is provided above and is taken from the book ‘Re-challenging & Reintroducing FODMAPs – A self-help guide to the entire reintroduction phase of the low FODMAP diet‘.  There are alternative protocols which can be initiated and I discussed another protocol with Alana from ‘A Little Bit Yummy’ in a very useful article linked here.


The table above provides an example of the types of foods that only contain one type of FODMAP and so are suitable for re-challenging. I discuss this more in an article I wrote with Nicer Foods (now FODY Foods) entitled TOP TIPS TO GET YOU STARTED WHEN RE-CHALLENGING FODMAPS.

Re-challenging can take up to 10 weeks to test tolerance levels to the 6 different FODMAPs. As each challenge typically lasts 6 days with the washout period many individuals tend to test a different FODMAP each week. Many food contain multiple FODMAPs which limits the amount of foods suitable for re-challenging therefore it is important to remember at this stage you are testing TOLERANCE LEVELS TO INDIVIDUAL FODMAPs so only use foods that contain one individual FODMAP. For more practical tips on re-challenging FODMAPs you can listen to a podcast I really enjoyed doing with Larah from

Reintroducing FODMAPs


What you are trying to achieve when reintroducing FODMAPs is to work out how many foods containing FODMAPs you can consume before you go over your FODMAP threshold and start to trigger symptoms. Everyone will have their own FODMAP threshold. The thing to remember is unlike re-challenging where you test your tolerance levels to individual FODMAPs – when reintroducing you are testing how many multiple FODMAPs as well as the overall load of FODMAPs you can consume before you go over your FODMAP threshold and trigger symptoms.

Modified FODMAP diet

Successful reintroduction of FODMAPs often means following a modified FODMAP diet in the long term to self-manage gastrointestinal symptoms. A modified FODMAP diet contains high FODMAP foods consumed within personal tolerance levels and allows the diet to be liberated from the restriction of a low FODMAP elimination diet. This is considered the best diet for long term gut health and can only be achieved through the reintroduction phase of the low FODMAP diet. For more information on a modified FODMAP diet see the article linked here: ‘Following the low FODMAP diet long term…What is a modified FODMAP diet?

A self-help guide to the entire reintroduction phase of the low FODMAP diet

For a full detailed explanation on re-challenging and reintroducing FODMAPs there is the first ever book dedicated to the entire reintroduction phase available on Amazon (Kindle & Paperback). There are difficulties in accessing current and reliable information on Reintroducing FODMAPs as I discussed in the linked article on the Food Maestro website and it is crucial this phase of the diet is done correctly to ensure unnecessary food restrictions are not continued long term. This best practice guide will walk you through reintroducing FODMAPs; including tables of all the suitable foods for re-challenging and which foods contain multiple FODMAPs, how to interpret your results along with case studies and an extensive FAQ on the difficulties of the reintroduction phase. For a continually updated and growing list of FAQ’s on the reintroduction phase of the low FODMAP diet check out our FAQ page.

Visit for more information on the book and FODMAP Reintroduction and for further information on the low FODMAP diet and private dietetic consultations.


↓Download: The Mini Guide to FODMAP Challenges and Reintroducing FODMAPs