What Is Leaky Gut Syndrome?

The father of modern medicine, Hippocrates, said, “All disease begins in the gut.” More than two millennia after his death, scientific research has now proven he was on to something all those years ago.

For over three decades, study after study has been published (several thousand articles exist to date) discussing our growing understanding of immunity, gut function, and how modern diets and lifestyles negatively contribute to overall health by damaging the digestive system.

I (and many others in the medical field) refer to this particular phenomenon as leaky gut syndrome. In the medical literature, leaky gut is also referred to as “increased intestinal hyperpermeability.”

What Happens When You Have Leaky Gut?

The intestines are protected by a single layer of specialized epithelial cells that are linked together by tight junction (or TJ) proteins. As one 2020 review explains, leaky gut symptoms are a consequence of intestinal TJ malfunction.

These TJ proteins are the gateway between your intestines and your bloodstream. They control what is allowed to pass into the bloodstream from your digestive system. More than 40 different TJ proteins have now been recognized to play a role in gut health.

TJ proteins have a very precise job. They have to maintain the delicate balance between allowing vital nutrients to enter your bloodstream, while remaining small enough to prevent xenobiotics (disease-causing substances like toxins and bacteria) from passing out of your digestive system into the rest of your body.

Here’s how a report published in the journal Frontiers in Immunology describes the pathology of intestinal permeability:

The intestinal epithelial lining, together with factors secreted from it, forms a barrier that separates the host from the environment. In pathologic conditions, the permeability of the epithelial lining may be compromised allowing the passage of toxins, antigens, and bacteria in the lumen to enter the bloodstream creating a “leaky gut.”


What is the main cause of leaky gut? As explained above, it occurs when certain tiny particles that should never be able to enter your bloodstream start to make their way through due to dysfunction of the mucosal barrier in the gut.

There also commonly are abnormalities in the gut stemming from antimicrobial molecules, immunoglobulins and cytokine activities. This presents a major problem, as the vast majority of your immune system is found inside the gut (sometimes called the microbiome).

The result is a disruption of acute inflammation and sometimes autoimmune reactions. A normal part of your immune response that serves to fight infections and diseases winds up over-performing, leading to chronic inflammation, which is at the root of most diseases.

Some of the underlying causes of leaky gut include:

  • Genetic predisposition — Certain people may be more predisposed to developing this condition because they are sensitive to environmental factors that “trigger” their bodies into initiating autoimmune responses.
  • Poor diet — Especially a diet that includes allergens and inflammatory foods, such as unsprouted grains, added sugar, GMOs, refined oils, synthetic food additives, conventional dairy products and alcohol.
  • Chronic stress
  • Toxin overload — This includes “chronic stressors,” such as high drug and alcohol consumption. We come into contact with over 80,000 chemicals and toxins every single year, but the worst offenders for causing leaky gut include antibiotics, pesticides, tap water, aspirin and NSAIDs. I recommend buying a high-quality water filter to eliminate chlorine and fluoride and look to natural plant-based herbs to reduce inflammation in your body.
  • Bacterial imbalance — Also called dysbiosis, which means an imbalance between beneficial and harmful species of bacteria in your gut. A large body of evidence now shows that gut microbiota is important in supporting the epithelial barrier and preventing autoimmune reactions. At least 10 percent of all gene transcriptions found in intestinal epithelial cells that are related to immunity, cell proliferation and metabolism are regulated by gut microbiota.

To read more about some of the problems that can develop due to gut dysfunction and possible treatments, click here.


I'm on a mission to create and promote gut-friendly food that is nutritious and delicious. Making food taste good is rarely difficult but making food consistently healthy and crave-worthy, well that takes effort. Food isn't neutral. Either it's helping or harming us. My goal is to create a table filled with real food that helps build a happy and healthy community.

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