Food Intolerances and IBS

Are Individualized Food Intolerance Tests the Key to Finding your Perfect IBS Diet?


Digestive Relief (Report 014): What diet is the best for IBS?Recent research coming out of Yale University shows us people with IBS are unique and different. Watch the episode below to learn more about what diet is best for you if you have Irritable Bowel Syndrome and struggle with ongoing gas, bloating, discomfort, pain, diarrhea or constipation.To get clear on your Triggers, download our checklist here

Posted by Stephanie Clairmont, RD on Wednesday, October 25, 2017


Carbohydrate Intolerance Diets

Many people who come to me looking for help figuring out what to eat to manage IBS symptoms have tried variations of low carb diets. Paleo, the Specific Carbohydrate Diet, and gluten-free are just some of the common ones. People will say these diets worked for them for a short time, but that their symptoms slowly started coming back, even though they hadn’t changed anything with their diet. Restricting carbohydrates is often the first strategy people turn to when they are trying to get rid of gas, bloating, distension, diarrhea, constipation and other symptoms. However, new research coming out of Yale University is showing us that people with IBS are unique and different, and that an individualized dietary approach may be what’s needed to successfully manage your symptoms. So, what’s the best diet for IBS sufferers?

Low FODMAP isn’t Low Carb

Low FODMAP is another common approach for IBS. The main difference setting this diet apart from the others previously mentioned is that the low FODMAP diet has lots of research behind it! It has specifically been shown to be effective in reducing symptoms in patients with IBS!

This is the diet I used to get to a place of living almost completely symptom-free with my IBS, and the same approach I take with my clients. As a Registered Dietitian, I only make recommendations based on sound science. This way, you know you’re getting only the most effective and safe strategies. This is my promise to you, and a major difference between seeking out the services of a Registered Dietitian for your food and nutrition related needs.

While the low FODMAP diet focuses on eliminating certain types of carbohydrates, it’s not really a low carb diet. The point is not to limit your carbohydrate intake, it’s just to be selective about which types of carbohydrates you are consuming, and limiting the ones that can be harder to digest.

Individualized Diet for IBS

A Yale team of researchers conducted a double-blind randomized controlled trial which included 58 people with IBS. This type of study design usually produces high quality, reliable results, since both the participants and researchers do not know which treatment participants are receiving. Sometimes, when participants know they are receiving a treatment, they tend to report feeling better just because they know they are getting something that is supposed to help them, even if it’s not really all that effective. A double blind study removes this possibility.

The researchers were seeing that many people changed their diet based on results from blood tests that claim to identify food intolerances, but many of these tests have not been validated (shown to consistently measure that they claim to).

Yale scientists used a specific blood test called a leucocyte activation test to determine immune cell response to specific foods. This test may be of greater clinical value than other food intolerance tests, however there isn’t enough research on this test to know for sure. In other words, it’s not worth seeking out this test as this point in time.

Once they performed the leucocyte activation test on the participants, the researchers placed each participant on a different diet in accordance with the results of their test. Some participants’ diets were consistent with the results (foods that were suspected as intolerances were restricted), while others were put on a diet that was purposely inconsistent with their results (they were encouraged to consume foods the test indicated they might be intolerant to).

After 4 weeks on the individualized diets, people were asked about their IBS symptoms and quality of life. The group on the individualized diet that was consistent with their test results saw a dramatic decrease in abdominal pain and bloating compared to the group that was consuming foods that the test indicated they shouldn’t be.

While this study lays the groundwork for more similar research to be performed, it shows the importance of an individualized approach to symptom management of IBS.


The Best Diet for IBS Sufferers

While the low FODMAP diet is what has helped me and so many of my clients, it’s not the most effective option for absolutely everyone with IBS! Following a strict low FODMAP diet by the book does not result in symptom relief for everyone. Some people with IBS actually find some high FODMAP foods don’t bother them, while others find that some low FODMAP foods don’t agree with them at all!

We are all a little different, and special in our own unique way, and our digestion and the way we experience IBS is no exception. While my approach to treating IBS uses the low FODMAP diet as a foundation, there are many ways I customize and individualize the diet for each of my clients so they can achieve the best possible results.

You need to get clear on your personal food triggers. This is why general advice on blogs and free food lists might not be helpful for you. And remember, symptom triggers don’t just have to be food-related, they can also be behaviours! You need to commit to a plan that was created for you so you can come to know your threshold for what your body can handle in a day and in a meal, and balance out that mind-gut connection.

I’m here if you need me, my friend!


Wishing you much love & wellness,



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