As a gut health dietitian, the vast majority of clients I see in my practice have a chronic inflammatory concern that manifests itself in digestive issues or auto-immune issues, usually with mental wellbeing challenges.

I am constantly asked: is leaky gut behind this? Unfortunately, the answer is rarely clear for the individual case. Which we’ll talk more about…but let’s start with what’s actually happening to your body when your gut barrier falters.

Your gut knows best about who should be allowed past the velvet ropes into your circulation and who – or what – should be passed on through to the porcelain bowl. You have a very sophisticated system of absorptive channels and transporters designed to optimize your intake of environmental goodies, which is why gut health nutrition is so critical. These features should be adequate to block immunogenic or harmful substances out of your body, until barrier dysfunction occurs.

What happens when a dysfunctional barrier allows more than its fair share through? This is known as the translocation of luminal contents – and it’s associated with an increasing number of chronic conditions1,2,6,7.

In the literature, which I comb through for my recent gut health Cookbook, leaky gut is noted in severe burn patients, HIV, celiac disease and inflammatory bowel diseases. You might expect this due to the active severity of disease; however, it’s also common in obesity and metabolic syndrome. In metabolic syndrome, it is thought that the translocation of bacterial fragments known as lipopolysaccharides causes inflammation that leads to insulin resistance2,7. Where is this coming from? As I discussed in part one, dysbiosis and inflammatory responses, often triggered by diet, infection or stress. However, an interesting question is whether or not the dysbiosis and gut barrier dysfunction cause disease or vice versa; another possibility is that the environmental conditions (like diet) that create both do so simultaneously.

The Microbiome at Home in Your Gut

For all of this talk of the benefits of a balanced gut flora, we don’t often state the obvious: that gut bacteria should stay in the gut if you don’t want any problems. When the gut leaks, fragments of bacterial cell walls can travel through the blood stream and accumulate in tissues, leading to chronic inflammation1,2,6,7. This sounds like crazy science fiction but in fact, a host of new research is looking at diseases like depression, type two diabetes and rheumatoid arthritis and finding deposits of bacterial fragments in the tissues – which contributes to the chronic inflammatory response2,6,7,9. You can see how this is a viscous circle: inflammation causes leaky gut, which increases translocation, which increases inflammation…this is why most people who suffer from these kinds of conditions have difficulty restoring their health.

Beyond more common chronic diseases, there is also a very intriguing hypothesis that gut barrier dysfunction and autoimmunity are linked6. This makes sense when you think that infection – which the body would perceive in leaky gut – predisposes to autoimmunity6,7.

There are multiple cell types and response patterns in the immune system; disruption of the gut flora (dysbiosis) can alter the TH17 balance7. TH17 cell types are associated with higher levels of inflammation and also associated with auto-immunity7.

The story here with leaky gut is that what happens in the gut doesn’t always stay in the gut, and that can be a problem. However, there is a very normal and critical communication between the brain and the gut occurring on a daily basis that makes restoring gut health even more critical to mental wellbeing.

The gut is connected to the brain by about a half a billion neurons, which transmit messages via the vagus nerve. And roughly 80% of that communication is coming from the gut to the brain. However, it is a two-way street and psychological stress is associated with diminished barrier function. I have experienced this firsthand: as someone who experiences gut health issues that also extend to my skin, I have adopted a plant-centred, anti-inflammatory lifestyle that allows me to feel 100% healthy most of the time. However, at least a couple of times a year, I let myself get overworked and the stress causes a flare of my symptoms.

Is it always food? And do you need to eliminate?

This is the biggie: our food culture is simultaneously one of super inflammatory dietary patterns filled with low nutrient, hyper-processed food and one filled with so much fear of eating the ‘wrong thing’ that leads us to blame everything on food.

We have not yet talked about translocation of partially digested food stuffs in gut barrier dysfunction. So let’s get controversial, shall we?

It is thought that gut barrier dysfunction will lead to the immune system being presented with larger food particles than it is used to seeing; for example, a protein or protein fragment instead of its amino acid building blocks. And this presentation could potentially lead to delayed sub-acute reactions to food, mediated by a molecule called IgG49.

IgG food sensitivity tests are often recommended by naturopaths and remain very controversial in the conventional medical community. One reason is that testing methodologies and substrates in laboratories are often not standardized, meaning that doing the food sensitivity test via multiple labs would yield multiple results. Not a great starting point for clinical science. I will talk more about whether or not I recommend these tests in part three. For now, let’s talk about how theoretically food could be contributing to inflammation and leaky gut.

If you have a classic IgE-mediated food allergy, it is a clear cut case: eat the food, have an allergic response. With food sensitivity, it’s far less clear: is the food the cause of the issue, or is the sensitivity a symptom of a larger root cause? My sense is that it is the latter, and gut barrier dysfunction is the key.

What does this mean? That no, gluten isn’t the gut devil. And yes, removing gluten might help fix your gut. If your immune system has labeled a food as harmful, eating that food will contribute to inflammation that would impair healing. And removing gut barrier disrupters like alcohol is wise for better healing. However, it’s an individual reaction – and clinical picture – that determines the way forward.

Is gut barrier dysfunction actually a problem? Or just a temporary setback?

You might have guessed by now that yes, gut barrier dysfunction can be a challenge for many and addressing it is a critical piece in an integrative, holistic model to restoring health. However, before we all go and freak out (because that’s not good for your inflammatory-gut-brain mojo!), you need to know that gut barrier dysfunction is very unlikely to occur in isolation and may not be a huge issue, particularly in the short term4. So, if you feel really good right now, don’t worry that you may have leaky gut just because you got stressed last week.

To further my point, alcohol is a known gut barrier disruptor (sigh!). If you’re healthy and drink moderately, but you decide to temporarily quit drinking (dry January, anyone?), you may feel a bit better and part of that could be the result of better gut function. The body is meant to heal and the gut is an incredibly dynamic, constantly regenerating tissue. Remove the aggressor, and generally, things will get better. We can use the zonulin example here too: in those with celiac disease, the zonulin system is upregulated and eating gluten means ongoing gut barrier dysfunction9. However, in healthy individuals, while gluten may impact the zonulin system, it is time-limited, minimal and reversable9.

Of course, if you have been finding your health diminishing and you have mental wellbeing/digestive/inflammatory concerns, you might expect there is some degree of challenge to your gut barrier. This is the time to take healing more seriously; know that improving gut barrier function needs to be a key part of your strategy.

Which leads to the big question: how do you know you have leaky gut?

Leaky gut remains a challenge in the medical community, no doubt in part due to the lack of gold-standard testing. Intestinal permeability tests are varied: oral challenge with EDTA, sugars and combinations with sugar alcohols and urine testing1. You may also receive blood testing for antibodies like TTG or zonulin1. However, these tests are fairly rare in practice. Go to your GP and ask for testing for leaky gut and see how it goes…which is why often in practice, I am assuming the presence of leaky gut based on the presence of other diagnoses (like severe IBS or autoimmunity).

If you have access to an integrative and functional medicine practice, it is more likely the physician will be well-versed and able to test for leaky gut. Otherwise, you might be on your own (or with me, your dietitian!)

Taking an Integrative Approach to Leaky Gut

Armed with a better understanding of gut barrier dysfunction, you can take a more intelligent approach to healing. Right now, there is no evidence-based gold standard therapy for improving gut barrier integrity but there are absolutely paths you can take to get better. That’s for another blog post…coming soon!

Photo by Tanja Heffner on Unsplash