Gluten. The very word conjures up all manner of wellness fear – needlessly, I might add. Of course, gluten is also connected to autoimmune responses in celiac disease and so we know in some cases it can drive chronic inflammation. But, does gluten cause inflammation for everyone? What if you’re dealing with other forms of chronic inflammation or autoimmunity like Hashimoto’s or arthritis? Is there any evidence to back up the claim that gluten is inflammatory? Let’s do a deep dive.
As a registered dietitian with a focus on both gut health and chronic inflammation, I get a LOT of questions about gluten. And, in order to be as inclusive as possible, most of the plant-based recipes on this blog are gluten free – and all of the recipes in Eat More Plants Cookbook are too. I want you to really understand how gluten might or might not cause inflammation, so you can fend off misinformation. So, we’ve got to start with the basics. First things first: do you know what inflammation is? You do? Awesome, we’re off to the races then…now let’s get clear on what gluten is too.
What is gluten?
Gluten is a naturally occurring protein in grains such as wheat, barley, rye and their derivatives. Gluten is what gives elasticity and structure to breads and baked goods. You can also use gluten (known as seitan) as a plant-based protein.
What makes gluten unique as a protein is that its amino acid structure (amino acids are the building blocks of proteins) has a lot of proline and glutamine amino acid bonds that are difficult for our digestive enzymes to fully break down.
When this happens, it means that partially digested gluten fragments – too big to be absorbed by our digestive system – remain in the gut and travel down the digestive tract to be excreted. Remember, anything fully digested and absorbed is a non-issue: if it’s not in the gut, it can’t interact with the gut! However, the fact that it isn’t fully digested and absorbed needn’t cause alarm either. For example, fibre isn’t digested and that stuff is GOLD for our digestive health. It’s one reason why dietary fibre is so important for fighting inflammation.
Is gluten bad for you?
For some people, like those with celiac disease, these partially digested gluten fragments can interact with the immune system and create an immune response. And since this is possible in some, it’s led others to speculate that gluten is ALWAYS inflammatory and ALWAYS bad for you and that’s just not the case.
Consider that gluten is part of our number one consumed grain: wheat. And that the research on whole grains shows quite clearly that consuming whole grains (as opposed to refined grain products) is associated with multiple positive health outcomes such as decreased risk of heart disease, type two diabetes and may also lower risk of inflammatory conditions such as rheumatoid arthritis. There is just zero controversy about this in the (human trials) science. But there is tons of imagined controversy about this on the internet – and even with some health practitioners – which means they aren’t paying attention to the science.
It’s kind of like saying that since some folks can be deathly allergic to almonds, almonds are bad for you. Even the least evidence-based wellness folks don’t say this about almonds. But wellness folks do (incorrectly) make this connection to gluten, peanuts and soy.
Does gluten cause leaky gut?
We have learned a great deal about the presence of leaky gut AKA gut barrier dysfunction in chronic inflammatory conditions such as celiac disease. While getting a ‘diagnosis’ of leaky gut isn’t legit, gut barrier dysfunction does exist. The causes of leaky gut are likely multifactorial and include stress, overall dietary quality, zinc deficiency and chronic NSAID use.
It is now understood that a molecule called zonulin that appears to increase gut barrier permeability, or ‘leakiness’. You’ve probably seen folks quoting research that gluten can increase gut permeability in everyone – not just those with celiac disease – so there is something you should know: currently, the research suggests that any increase of permeability outside of celiac disease is transient (meaning it repairs quickly). Permeability shifts are also much milder in those without celiac disease. It’s also worth noting that while gluten can trigger zonulin release in those who are sensitized to it – so can bacterial dysbiosis and perhaps this is the bigger sensitizing event particularly when it comes to chronic conditions.
So yes, gluten appears to be able to increase gut permeability in some folks…but it is a major overreach to say that it is THE cause of gut permeability in everyone. And, it’s unlikely that leaky gut is the only thing causing your inflammation (but it may contribute!). What is likely is that the stronger culprit is an imbalanced gut microbiome and the best way to fix that is with a whole plant food-focused diet that INCLUDES whole grains.
Gluten and Joint Pain
If you have joint pain, will cutting out gluten help? The literature doesn’t give us a lot to go on here. Celiac disease and gluten neuropathy aside, non-celiac gluten sensitivity has been associated with symptoms of joint pain but the quality of evidence isn’t very high.
In rheumatoid arthritis (RA), which shares autoimmune links with celiac disease, we don’t have enough evidence to suggest that gluten worsens symptoms. Interestingly, one trial of a gluten free vegan diet showed improvements but it is impossible to say whether the gluten free aspect of that study mattered or if it was just the vegan diet. Also, it was only 2 trials…not much to go on. One case report suggests that some may benefit from going gluten free. Other work suggests that whole grains should be part of a dietary approach for RA.
So while I do believe that we should support rheumatoid arthritis with nutrition, we definitely can’t say that it should be gluten free nutrition. Remember that when we make dietary changes, such as going gluten free, it can sometimes be tough to tease out what exactly worked. For example, was it really losing the gluten? Or did you also eat a lot more nutrient-dense whole foods.
Gluten Free Diet for Hashimoto’s
Going gluten free is commonly recommended for those with Hashimoto’s, a common autoimmune condition that causes low thyroid function. Read my full length blog on Hashimoto’s nutrition for the scoop.
Do you need a gluten free diet for inflammation? Does gluten actually cause inflammation?
The most exact advice I can give for this question: YOU might benefit a gluten free diet to help control your inflammation…but going gluten free isn’t anti-inflammatory for all. Does gluten cause inflammation for everyone? Nope.
If these statements seem contradictory, let me clarify:
- gluten isn’t an ‘inflammatory food’ and in fact, gluten-containing foods such as whole grains (within the context of a healthy, high fibre diet) are associated with lower inflammation
- however, for any one person, a certain food or component of foods may make symptoms worse. This is akin to how someone with an almond allergies can’t eat almonds even though almonds are healthy for most folks.
So what to do? First things first: if you are trying to lower chronic inflammation, first work on a general healthy eating pattern associated with an anti-inflammatory diet. This will help you increase fibre and intake of phytochemical-rich plant foods that support overall health and a healthy microbiome. If that isn’t giving you enough relief, get one-on-one advice from a registered dietitian to help you sort out which foods are best to help YOU thrive given your unique needs.