Gluten and fodmaps

Updated on July 31, 2023.

Let’s go back to the basics, because there’s a lot of confusion.

There are a few subtleties to be aware of, but in itself, it’s quite simple.

Regarding fodmaps

The low fodmap diet has nothing to do with gluten. Gluten is not part of the restrictions.

Fodmaps are all carbohydrates (sugars), while gluten is a protein.

But with fodmaps, you should avoid wheat, spelt, baby spelt or barley for example, which also contain gluten.

Does that mean that it’s the same thing then?

No, because some gluten-containing ingredients are not high in fructans, such as certain oat flakes.

Others are high in fructans but do not contain gluten like onions, melons, asparagus or dates. To generalize would therefore be to make mistakes, to consume foods that should be avoided and to avoid some that do not pose a problem.

A distinction is made between cereal fructans and fruit and vegetable fructans. For example, some people are sensitive to fruit and vegetable fructans like garlic, but not to wheat and other cereals. They are not really different types of fructans, in fact they are exactly the same, just the fructan level in fruit and vegetables is often higher than in cereals, which can make a difference for some people.

It is true that on a practical level, if you search for recipes on the internet for example, searching for “gluten-free” will give you much more results and it will almost always be in line with the fodmap diet for fructans, as long as you are in a period of exclusion or if you have detected an intolerance to fructans. But keep in mind that gluten is not the problem.

Beware, the goal is not to eliminate purely and simply the ingredients containing fructans, simply those high in fructans. It allows you to eat small amounts of certain ingredients and that changes everything. Since a maximum of 0.2 gram of fructans per meal is allowed, this means that a slice of bread with wheat flour is allowed for everyone, even during the exclusion period! (no more, mostly).

So please replace “gluten” with “fructans” in the future! 🤗

Celiac, sensitive or allergic to gluten?

The first part of this article focused purely on the relationship between gluten and the fodmap diet, which is mostly a misunderstanding and gluten has no place in the restrictions of this diet.

But a lot of gluten-sensitive people are becoming interested in fodmaps. Or at least they should. Let’s look at the different possible cases:

Allergies to gluten or wheat

Like any food allergy, these people will have symptoms in the area of respiratory, skin or digestive problems. This is quite rare (about 0.3% of the population) and is very easy to diagnose when a blood test is taken, because they produce an antibody (IgE).

Celiacs

A disease that totally forbids the consumption of gluten, under penalty of damage to the small intestine. This disease is also easily diagnosed by a blood test thanks to the presence of another antibody (IgA).

Between 0.4% and 1.4% of the world population has this disease, even though most are un-diagnosed (around 80% in the US for example).

Non-Celiac Gluten Sensitive (NCGS)

This is what is commonly known as gluten intolerant people, people who are neither allergic nor celiac but who nevertheless claim to be better by avoiding gluten.

Non-celiac gluten sensitivity is estimated to reach between 0.5% and 13% of the population, the calculation methods are very varied and it is a very difficult subject to grasp. 

To date, there is no clearly established scientific rationale where the role of gluten has yet to be demonstrated.

AFDIAG

It is a global consensus of the scientific community, not a bias.

Everything you need to know about the fodmaps and gluten diet, what is and is not allowed. There are important subtleties to know!

But how do you explain that these people get better when they no longer eat wheat?

A great classic is that these people did not do a test to rule out celiac disease, or were ruled out by mistake, which represented 62% of people in a 2014 study!

Fructans rather than wheat cause problems for people who are gluten-intolerant

Another lead is that these people, often self-diagnosed (there is no real sure diagnosis, it is simply by rejecting the celiac and wheat/gluten allergic hypotheses that we can classify people as non-celiac gluten sensitive), are in fact intolerant to fructans and not to gluten.

This lead has been scientifically validated by the co-inventor of the FODMAP diet and is a serious lead for anyone who sees improvements in avoiding wheat but for whom this does not solve all the problems.

In practical terms, this amounts to almost the same thing (restrictions on wheat essentially), but it allows us to clearly identify the other food families to be monitored. The scientific basis of fodmap is more substantiated and consistent than that of the NCGS, which puzzles many scientists.

Gluten or fodmap, science still has plenty of room for progress. Let’s not deceive ourselves, we are only at the beginning.

Far be it from me to liken all gluten-sensitive people with irritable bowel syndrome, but it is something that could be explored.

You have to distinguish between two types of people:

• Those who only have digestive problems: in this case, it is very likely that you have an irritable bowel syndrome and fodmaps will be a very interesting avenue to explore.
• Those who suffer from headaches, muscle and joint pain and fatigue, as well as digestive disorders. In this case, you are much more likely to be hypersensitive to gluten, unrelated to IBS.

Once again, this is only a lead, do not self-diagnose and do not get into fodmap: if you recognize yourself there, go and see a gastroenterologist to make the right diagnosis, it is essential.

You have been diagnosed as gluten intolerant

By intolerant, I mean non-celiac gluten sensitive as explained above.

And if you have been diagnosed with such intolerance, you may have had a blood test that cost you a lot of money and was not reimbursed. Please note that gluten intolerance cannot be detected by a blood test.

I’m not saying that everything should be thrown away: if you get better by eating less / more wheat, that’s all that matters and keep going like that. But don’t be fooled by unscrupulous labs and maybe question other intolerances that they have certainly detected, they are likely to be far-fetched and potentially harmful.

Sources

• Characterization of Adults With a Self-Diagnosis of Nonceliac Gluten Sensitivity, a 2014 research paper, co-written by Sue Shepherd and Peter Gibson, who are behind the fodmap diet.
• Global Prevalence of Celiac Disease, Celiac Disease Association, August 2018.
• Fructan, Rather Than Gluten, Induces Symptoms in Patients With Self-Reported Non-Celiac Gluten Sensitivity, a 2018 research paper
• Celiac disease, by AFDIAG, the French celiac disease association.
• Non-Celiac Gluten Sensitivity: A Review, a 2019 research paper.