Avoiding gluten seems to be all the rage these days. People do it for many reasons:
- Weight loss
- Gut health
- Overall health
- Allergy or intolerance
Many should avoid gluten, such as those with celiac disease or a gluten sensitivity/intolerance. But should your everyday average Joe or Jane ditch gluten? Is gluten the newest scourge to humans?
Or is it simply one of the many things that a small number of people should avoid? Let’s dig in to the evidence.
The experiment showing everyone should be avoiding gluten
The most often cited paper as evidence that gluten is bad for everyone really doesn’t show that. So what does it show?
The paper in question took tissues samples from the small intestine and exposed them to gluten fragments. But why gluten fragments?
Well, because gluten in it’s normal form is benign. It’s not until our digestive enzymes and microbiome break it in to gliadin fragments that it becomes problematic.
And in this study, it was indeed problematic. Tissue samples from all people, including healthy individuals, had increased intestinal permeability when exposed to gluten.
As a result of exposure to gluten, all samples showed leaky gut. In people with active celiac disease, it was way worse. But even those in remission and healthy controls saw increased permeability.
So there you have it. Everyone should be avoiding gluten, right? Not so fast.
The weird and wonderful microbiome
One of the many beneficial things that our microbiome does for us is help break down our food. While it’s true that we don’t make the enzymes to effectively break down gluten, our microbiome does.
In fact, some of those members likely play a starring role in converting gluten to gliadin. On the other hand, others break gliadin up in a way that makes it benign.
In fact, a recent paper in children found that the saliva is a rich source of gluten-degrading bacteria. Furthermore, healthy children had a higher proportion of gluten-degrading bacteria than those with celiac disease.
Of course, if you expose extracted small intestinal tissue to gluten fragments, you bypass the saliva. This is one of the reasons that paper on ex vivo tissue samples isn’t very representative of what happens.
Between our protein digesting enzymes and those of our microbiome, some of us break down gluten just fine. However, the less fortunate convert gluten into something that can cause problems.
This is no different than foods that are common allergens like eggs or peanuts. They are fine for some, but not others. But it doesn’t mean that everyone should avoid gluten.
In fact, there may be some drawbacks to doing so. We covered this topic in our most recent Youtube video you can check out here:
Drawbacks to avoiding gluten
Let’s face it, gluten isn’t an essential nutrient. You don’t need it in your diet and it probably isn’t doing anything special for you.
However, maybe you’re in weight loss mode right now and think a gluten free diet may help you. Conversely, maybe you have IBS and want to remove gluten from your diet permanently because you think it’s causing symptoms.
These are completely different scenarios from a person with celiac disease or non-celiac gluten sensitivity(NCGS) removing gluten. And there may be repercussions to removing it.
In healthy people, a long term gluten-free diet may not be the best idea. A recent review shows that a gluten-free diet leads to detrimental impacts on the microbiome of healthy people.
In healthy individuals, a gluten-free diet increased the abundance of potential pathogens such as Enterobacteriaceae and Escherichia coli. In addition, there is a decrease in beneficial microbes such as Faecalbacterium, Lactobacillus and Bifidobacteria.
It’s interesting that the both of the former actually participate in the degradation of gluten(See top image). Therefore, a prolonged gluten-free diet may impair a healthy person’s ability to degrade gluten.
Interestingly, people with celiac disease see similar changes. However, they see a drop in pathogenic Proteobacteria too. This is likely due to decreasing inflammation in those with celiac disease consuming gluten.
So while there are drawbacks to both, a healthy person removing gluten sees none of the benefit.
A gluten-free diet is a godsend for people with celiac disease and NCGS. But many people believe that everyone should be avoiding gluten. This is not the case.
A healthy person that removes gluten will likely see negative changes to their microbiome. A good portion of this comes from the removal of complex polysaccharides that come packaged with gluten.
If the gluten-free diet is prolonged, this could reduce the gluten-degrading capacity of the individual. Ultimately, this could create an intolerance to gluten that didn’t previously exist. In an otherwise healthy individual, prolonged removal of gluten is likely a bad idea if you want it back in your diet eventually.
Trialing a gluten-free diet for a month or 2 followed by reintroduction is likely safe if you do not have celiac disease or NCGS. If you have IBS, the low FODMAP diet elimination phase is perfectly fine. However, if you like gluten containing foods you may want to reintroduce them first.
Interestingly, a recent study found that adding supplemental gluten to a low FODMAP diet caused no detrimental impact in 80% of IBS patients. This means that only 20% had a true problem with gluten. And this data is not new, previous studies found many self-diagnosed with NCGS actually have a sensitivity to FODMAPs.
In essence, most are reacting to fructans and not gluten. Unfortunately, most assume the problem is gluten, and gluten-free breads tend to contain fructans. This is why a pragmatic approach to identifying problematic food components and reintroduction is important.