Gluten vs Fructan? Who's the culprit?

When coaching my clients to learn how to follow a low FODMAP diet for the elimination of IBS symptoms, and then taking them through the process of testing with careful reintroduction, I am often told “I’m gluten-intolerant” or “gluten makes me feel terrible.” I actually love to hear this from my clients because, while it has been long assumed that gluten is a trigger for IBS symptoms, we have learned that it’s more likely to be the fructans in bread that are the trigger. And that’s a game changer.

Article authored by Ketan Vakil, of Gourmend Foods

Within the low FODMAP/IBS community, it is well known that those with IBS should avoid gluten. Whether or not you have a proven gluten intolerance, you've probably been told that you should avoid it altogether.

But what if gluten isn't the problem? 🤔

If you use the Monash University app that gives you their well-tested guidelines (and we highly recommend it, it's great!), you will see that not all flours and breads are off-limits on the low FODMAP diet. While anyone with celiac disease should avoid gluten entirely, those who are non-celiac and on the low FODMAP diet can have certain types of breads and flours. For instance, sourdough bread is safe, even though it is usually made with wheat.

It's important to note that bread not only has gluten, but it also contains fructans (an oligosaccharide), which is a well-known IBS trigger.

While it has been long assumed that gluten particularly triggers IBS symptoms, what if it's the fructans in bread that are the trigger? The scientists who performed this study, published in the journal Gastroenterology (one of our absolute favorite studies!) wanted to learn just that.

They recognized that those with non-celiac gluten sensitivity have symptom relief after gluten is removed from their diets, but that didn't necessarily mean that the relief was from not consuming gluten. What if they felt relief by removing something else from their diets? Something like fructans!

59 participants with non-celiac gluten sensitivity were given a bar with gluten, fructans, or neither to see how they responded.

The results showed fructans were actually more likely to produce symptoms than gluten: 13 participants experienced the worst symptoms after eating the bars with gluten, while 24 reported feeling worse after eating the fructan-rich bars. Interestingly, 22 said the placebo bars bothered them most.

As it turns out, gluten may not be the IBS instigator that we have assumed it is!

This study actually validates why sourdough bread is safe to consume.

Have you ever wondered why sourdough bread can be safely enjoyed on the low FODMAP diet, even though it has gluten? Sourdough is low FODMAP because there is a fermentation step in the process of creating sourdough bread that decreases the fructan content. Even though there is still gluten present, the absence of fructans makes it safe for IBS sufferers.

That being said, not all sourdoughs are made equal. We recommend finding a local bakery that makes their own. The fermentation process for sourdough is lengthy, and buying from a trusted local bakery or making it yourself guarantees that it will be done right.

How can you tell if the sourdough at your local bakery is the real deal? Hint: it should have only 3 ingredients (wheat, water, and salt)! 

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