The Elimination phase of the low FODMAP diet is the first step identifying food triggers for your IBS. The central goal of the elimination phase of the low FODMAP diet is to find out if removing FODMAPs from your diet will significantly reduce or eliminate your IBS symptoms.
Before you start
Before jumping into the low FODMAP elimination phase, its important to make a trip to your doctor. IBS type symptoms can be very similar to symptoms caused by other medical conditions including celiac disease, IBD (Crohn’s or Colitis), and even certain cancers. Your doctor will be able to assess you for any “red flags” that may need investigating first and order a blood test for celiac disease. It is important to do this before changing your diet as the test for celiac disease in particular will be inaccurate if you have already removed gluten from your diet.
The low FODMAP diet is restrictive, it can limit access to certain nutrients and effect lifestyle. Certain foods and behaviors can also influence IBS symptoms, so try other healthy habits like regular meals, eating slowly, limiting alcohol, coffee or spicy foods, managing stress, getting enough fiber, fluids, exercise or sleep first.
When to start?
There is no real rule here, but it does involve making changes to your diet, so you will need to be ready and able to do this without compromising your health. With this in mind, if you are about to go travelling or have a series of social engagements coming up, these may effect how easily you are able to follow the low FODMAP elimination diet and a different approach may be necessary.
Do I need to eliminate all FODMAP groups?
During this phase, it is important to remove all possible triggers from your diet. FODMAPs cause symptoms when they reach the colon, at the end of the very long digestive tract so symptoms take anything from 6 hours to 24 hours for a reaction to occur. This makes it hard to identify specific trigger foods, so even if you think you tolerate a FODMAP, it’s still important to remove it from your diet during this phase.
What can I eat?
The low FODMAP diet is just over ten years old, in terms of medical interventions this is a very short time. This means that science is moving very quickly and written information goes out of date very quickly. Save yourself some stress, see a FODMAP dietitian and download the FODMAP Friendly app. This app gets updated regularly as new information becomes available as well as being portable, so you always have it when shopping, out at a restaurant or café or at a friends’ house.
Do you need to keep a food diary?
In most cases I do not encourage my patients to keep a food diary. In my experience I’ve found food diaries cause extra stress by making people unnecessarily consumed with details. If your symptoms are settling this indicates that you have removed FODMAPs successfully. If after 4-6 weeks you are still getting symptoms, its worth doing a food diary to take to your dietitian to identify if there are sneaky FODMAPs getting in or if in fact there are other molecules in foods that may be a problem for you, either as well as or instead of FODMAPs.
Is the low FODMAP diet Gluten Free?
The low FODMAP diet is not a gluten free diet. Gluten is the protein in wheat, barley and rye. FODMAPs are the carbohydrate in wheat, barley, rye, certain fruits and vegetables, some nuts and beans, milk and milk products. Not all gluten free products are low FODMAP. Many high FODMAP foods, like fruits, vegetables, beans and milk are naturally gluten free. Likewise, many gluten containing foods, like soy sauce, have low FODMAP serve sizes. When buying gluten free products, it is still important to check for high FODMAP ingredients. Some examples of ingredients to look out for are:
- Besan or chickpea flour
- Lentil flour
- Soy flour
- Dried fruit
How long to follow the elimination phase?
The elimination phase of the low FODMAP diet is recommended to be followed for 2-6 weeks. Symptom relief can occur in as little as 3-4 days or may take a little longer. If you have been on the low FODMAP diet for 2-6 weeks and have had a significant reduction in symptoms for at least five days in a row, you are ready to start considering a reintroduction schedule. If after 6 weeks, you still haven’t experienced good symptom relief, you will need to trouble shoot with a FODMAP dietitian to determine whether to continue, or dismiss FODMAPs as the cause of your symptoms and explore other treatment pathways.
Elimination is restrictive, but its not forever diet. It is an essential part of identifying your triggers for IBS symptoms.