If you spend any time on natural health websites or with alternative medicine practitioners, you may have heard of ‘leaky gut syndrome’. What does that even mean? Can your gut leak like a tap and cause all sorts of health issues like some people say it can? 

The term ‘leaky gut’ isn’t recognized as something legit by the mainstream medical community, but it’s a commonly used by naturopaths, integrative doctors, and nutritionists (not dietitians) to explain a cluster of symptoms that nobody has otherwise been able to diagnose. If you search ‘Leaky Gut’ online, you’ll come up with a ton of garbage sites like Dr. Jockers, Dr. Axe, and the National Candida Center (OMG.). It’s definitely not a term commonly used in the science-based community.

What Is The Gut?

Just so you have a bit of background, let’s talk briefly about the gut and what goes on in there.

When we say ‘gut’, we generally mean the digestive system. 

The cells that line the intestines are called the intestinal epithelium, and they normally form a barrier to prevent unwanted substances (like pathogens) from escaping the intestine (smaller particles, such as nutrients, can pass freely). The spaces between the cells are called junctions, and these are normally tight against each other.

Zonulin, a protein, controls how tight those cell junctions are. When concentrations of zonulin are high, this is thought to signal an increased gut permeability. Some of the stimuli that trigger zonulin release in the gut are gliadin (the protein in gluten) in celiacs; infections; autoimmune diseases, and allergies. 

Sometimes, the intestines become more permeable, which is what we call ‘increased intestinal permeability’, or colloquially, ‘leaky gut’. When increased intestinal permeability is present, toxins and antigens from the gut leak out of the intestines, which can cause an immune response by the body. We believe that this immune response may be linked to conditions such as inflammatory bowel disease, celiac, and food allergies, among others.

Let’s get one thing straight: There aren’t particles of food floating around in your bloodstream.

So What Is Leaky Gut? Is It Real?

Tamara Duker Freuman RD, Author of The Bloated Belly Whisperer, tells me: “The bacterial byproducts or macromolecules come into contact with various immune cells in the lamina propia, which is a sublayer beneath the first layer of intestine. Remember: if bacteria make it into the bloodstream, you get sepsis and die. If food particles make it into the bloodstream, you get embolisms and die.”

She goes on the clarify, “There are 4 layers of gut, and the leakiness takes place within sublayers of just one single layer of the gut…this is the nuance that gets lost in the naturopath version of “leaky gut syndrome” and the actual scientific phenomenon of ‘intestinal permeability’, whose mechanism is believed to be immune activation WITHIN the gut. Bloodstream not really involved…”

A compromised gut barrier may precede the development of some diseases such as lupus, celiac, and type 1 diabetes, but this has been shown only in rat studies.

There’s no evidence showing that increased intestinal permeability is cause or a symptom of certain conditions. Which came first, the permeability, or the disease? We’re not sure, and not everyone is on board with this hypothesis:

The Canadian Society of Intestinal Research calls leaky gut a myth: 

The Myth: According to the proponents of leaky gut syndrome, bacteria and toxins enter the bloodstream through these defective tight junctions and wreak havoc throughout the body, causing bloating, gas, cramps, inflammatory bowel disease (IBD), as well as fatigue, food sensitivities, joint pain, moodiness, irritability, sleeplessness, autism, and skin problems like eczema and psoriasis.

Debunked: This is all speculation, as scientific studies do not validate any of these claims. It is extremely dangerous that a TV doctor personality and some otherwise trusted practitioners are diagnosing and treating this baseless ‘syndrome’.

Okay then! Did anyone catch the shade they threw at Dr. Oz? Excellent.

I’m not so sure they’re exactly right about saying that ‘leaky gut’ is a myth, though. 

We do know that increased intestinal permeability exists. We just aren’t sure that it causes issues systemically, and although they’re frequently advertised as such, we don’t know if any of the conditions listed above are the result of ‘leaky gut’. 

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What Causes Increased Intestinal Permeability?

A compromised intestinal barrier can be caused by high stress levels, NSAIDs, alcohol consumption, radiation and chemotherapy, trauma, and infection.

We also know that harmful gut bacteria can chew through the mucus layer that lies on top of the gut lumen (aka the intestinal wall), exposing the cells and impairing gut barrier function. 

Genetics also play a role: some people are at greater risk of reactivity to gluten, for example, and some are born with a trait that makes them more susceptible to increased gut permeability.

Conditions such as inflammatory bowel disease, toxins in food (aka food poisoning), celiac, and irritable bowel can also affect the permeability of our gut. 

The Symptoms of Leaky Gut?

Symptoms of ‘leaky gut’ are vague and similar to symptoms of many other conditions. 

Most people will complain of gas, bloating, cramping, brain fog, food allergies and intolerances, asthma, acne and other skin conditions, and fatigue. 

There are a lot of ‘doctors’ and other practitioners who use fear and bad science to sell ‘leaky gut’ to unsuspecting and vulnerable people. 

A particularly infuriating article by an MD on MindBodyGreen (which is a cesspool of bad nutrition information) states the following:

11 Signs You Have a Leaky Gut

1. Digestive system issues such as gas, bloating, diarrhea or irritable bowel syndrome (IBS).

2. Seasonal allergies or asthma.

3. Hormonal imbalances such as PMS or PCOS.

4. Diagnosis of an autoimmune disease such as rheumatoid arthritis, Hashimoto’s thyroiditis, lupus, psoriasis, or celiac disease.

5. Diagnosis of chronic fatigue or fibromyalgia.

6. Mood and mind issues such as depression, anxiety, ADD or ADHD.

7. Skin issues such as acne, rosacea, or eczema.

8. Diagnosis of candida overgrowth.

9. Food allergies, food sensitivities or food intolerances.

10. Poor immune system

11. Arthritis or joint pain

None of these are signs that you definitely have a ‘leaky gut’ and there is no reliable evidence to prove that ‘leaky gut’ causes any of them. 

My issue with this sort of listicle is that many of the people who write them go on to say that these conditions can be cured simply by fixing the ‘leaky gut’ problem. This is completely untrue.

Curing your ‘leaky gut’ will probably not cure your depression, your PCOS, or your food allergies, and to suggest that it will is irresponsible. 

Furthermore, systemic candida is a diagnosis that’s pushed by the same people who want you to believe that your leaky intestines are causing everything that ails you. 

There’s no reliable way to diagnose ‘leaky gut’, and no reliable way to assess if it’s ‘cured’, which leaves a great opportunity for scammers to convince you that you have this condition and then to $ell you the ‘cure’. Typical grift. 

Testing For Leaky Gut

Stool analysis, urine lactose:mannitol tests, and the ELISA test are all used by alternative practitioners to detect leaky gut, but none these tests are recognized as being efficacious for detecting the condition.

Healing Impaired Barrier Function

If you have any disease or condition, ignoring your doctor and trying to cure it with diet alone isn’t a great idea. In many cases, healing your gut isn’t going to actually take care of the underlying disease, so take the medicine your physician prescribes, and work with an RD who specializes in your condition.

If you are having any symptoms that you think are related to your gut, the first thing I’d suggest is to try to protect and optimize your intestinal barrier and see if those symptoms improve, by doing the following things:

Reduce or cut out NSAIDS and alcohol to protect the gut from more damage.

Reduce highly refined and ultra-processed foods, as well as added sugars, which can cause negative changes to the microbiome.

Eat tons of vegetables, prebiotics, fermented foods, healthy fats, and fiber-rich grains, which all nourish good gut bacteria.

Cut out gluten only if none of the above has any effect on your symptoms, and speak to your doctor and an RD for support and monitoring.

Supplements for Leaky Gut

Glutamine is very often recommended to heal leaky gut. While it’s most likely safe, studies on how it alleviates or protects from gut permeability are mixed. 

Probiotics may help heal the gut, but we aren’t exactly sure which strains are most effective for this. S. Boulardii is sometimes prescribed as a probiotic for intestinal permeability, but 

Zinc may enhance the intestinal barrier, according to some studies. 

So, Increased Intestinal Permeability Does Exist. 

But so do people who hijack and exploit the term for their own gain. 

Unfortunately, restoring the intestinal barrier doesn’t cure things like autism and diabetes, so don’t believe anyone who tries to sell you on that idea. Most diseases and conditions are far more complex than a simple increase in intestinal permeability. 

Random supplements and cures, scare tactics and diets, are not going to heal your impaired intestinal permeability or your chronic conditions. Don’t buy in to any of that. You don’t need to spend $14 on a cup of bone broth to heal your leaky junctions.

It appears as though increased intestinal permeability may be due to different causes, some of which may be fixed with alterations to diet and lifestyle.


Title photo credit: IStock Photo