Leaky Gut Syndrome: Causes, Symptoms, and Solutions for Gut Healing

Leaky Gut Syndrome, though often overlooked, is a common feature of chronic disease of many kinds. The exact phrase “leaky gut” is not usually found in the medical literature, though it is used to describe the process increased permeability of the intestinal barrier. The correct medical terminology for this is intestinal permeability.

What is Leaky Gut Syndrome?

The lining of your intestines act as a barrier that selectively allows nutrients to pass through and blocks toxins and harmful substances from entering your body. The weakening of this barrier leads to increased intestinal permeability, or what we call “Leaky Gut Syndrome”. When the lining of the intestines becomes permeable, this facilitates the free passage of toxins, bacteria, and undigested food particles into the bloodstream. This process can trigger the immune system and has been associated with systemic inflammation. The result? A series of inflammatory responses that can trigger a multitude of symptoms throughout the body.

Leaky Gut 1

Di Vincenzo, F., Del Gaudio, A., Petito, V. et al. Gut microbiota, intestinal permeability, and systemic inflammation: a narrative review. Intern Emerg Med 19, 275–293 (2024). https://doi.org/10.1007/s11739-023-03374-w

Symptoms of Leaky Gut Syndrome

  • Digestive issues such as bloating, gas, diarrhea, and constipation
  • Food sensitivities or allergies
  • Chronic fatigue and low energy levels
  • Joint pain and inflammation
  • Skin problems like acne, eczema, or rosacea
  • Mood disorders such as anxiety, depression, and brain fog
  • Autoimmune conditions such as rheumatoid arthritis, lupus, or Hashimoto's thyroiditis

But before we get into the details of the causes of Leaky Gut Syndrome, and how to heal it, we should examine how prevalent this actually is.


Heightened intestinal permeability has been demonstrated in the following conditions:

  • Autoimmune Diseases: Celiac disease, type 1 diabetes, autoimmune hepatitis, multiple sclerosis, systemic lupus erythematosus and several other forms of autoimmunity have been linked to intestinal permeability syndrome and excessive bacterial translocation (ref)
  • Psychiatric Disorders: Depression, anxiety, bipolar, schizophrenia (ref)
  • Chronic Kidney Disease and Heart Failure (ref)
  • Inflammatory Bowel Diseases: Conditions like ulcerative colitis and Crohn's disease exhibit abnormal gut barrier function with increased intestinal permeability (ref)
  • Functional Gastrointestinal Disorders: Irritable bowel syndrome (IBS) and functional dyspepsia (FD) and small intestinal bacterial overgrowth (ref)
  • Metabolic Disorders: Obesity, metabolic syndrome and diabetes (ref)

What causes Leaky Gut Syndrome?

The role of diet

High consumption of processed grains, gluten, and refined sugar can lead to a damaged intestinal lining and disrupt your gut function.

  • Processed foods are usually high in preservatives, unhealthy fats, and additives. These substances are toxic for your gut and can lead to inflammation and irritation in your gut.
  • Gluten, a protein found in wheat, rye, and barley, has been associated with intestinal permeability, especially among those who have gluten intolerance. Ingestion of foods with gluten can trigger an immune response in these individuals, damaging their intestinal lining.
  • Other plant defense chemicals capable of triggering Leaky Gut Syndrome include lectins and oxalates, which are found in many vegetables, grains and legumes.
  • Refined sugar, with excessive consumption, can disrupt the bacteria balance in your gut and lead to growth of harmful microbes. This imbalance in the gut can lead to inflammation and disrupt the intestinal barrier.
  • Seed oils containing high levels of omega-6 polyunsaturated fatty acids


Stress induced hormones can weaken the barrier in your intestines, making them vulnerable and highly susceptible to damage.

  • Chronic stress triggers release of stress hormones that can have a damaging effect on your gastrointestinal tract. Excessive release of these hormones can increase the intestinal permeability and gut inflammation.
  • Unmanaged stress can also have a negative impact on the gut motility, changing the way food moves through your digestive system. The altered gut motility can worsen the intestinal lining, disrupting the gut function and leading to a leaky gut.


Antibiotics and Non Steroidal Anti Inflammatory drugs (NSAIDs) can lead to compromised gut health.

  • While antibiotics are important to treat bacterial infections, their consumption can lead to disruption of the gut bacteria balance. This disruption can cause an overgrowth of the harmful bacteria in your gut and an inflammation.
  • NSAIDs or Non Steroidal Anti Inflammatory Drugs (like Aspirin and Ibuprofen) can cause gut irritation and damage the intestinal lining, causing leaky gut syndrome.
  • Other medications including:

Environmental toxins

Toxins in the environment like pollutants and pesticides can lead to increased intestinal permeability:

  • Pollutants like pesticides, heavy metals, and industrial-grade chemicals can lead to toxicity in the gastrointestinal tract, damaging the intestinal lining and causing a leaky gut.
  • Food contaminants like additives can also cause inflammation in the intestines and compromise the integrity of your gut barrier.

Gut Microbe Imbalance

An imbalance in the gut microbes or gut bacteria can also compromise your intestinal lining, eventually compromising your overall gut health.

  • Dysbiosis, an imbalance in the gut microbiota, is caused when there is an overgrowth of harmful bacteria and decrease of the good bacteria in the gut. This imbalance can happen due to any of the above-mentioned factors. Dysbiosis ultimately leads to damage of the intestinal lining, causing Leaky Gut Syndrome.
  • Infections involving pathogenic bacteria, parasites, or viruses can also disrupt your gut microbe balance and lead to inflammation and permeability in the intestines.

A limited understanding of these factors and how they impact your gut health can keep you from making informed and healthy lifestyle choices, adversely affecting your gut and overall health.

An overlooked cause: Vagus Nerve dysfunction

The vagus nerve is responsible for communicating messages from the brain to the gut, and back in the opposite direction. As a key component of the parasympathetic nervous system, it is responsible for telling the digestive organs what to do and at what times.

Messages travelling through the vagus nerve are necessary for instructing the gut to perform several essential functions:

  • Stomach acid secretion and muscle propulsion
  • Digestive enzyme release from the pancreas
  • Intestinal secretion of brush border enzymes
  • Intestinal motility and mucous production

Vagus Nerve

Source: https://socratic.org/questions/does-the-vagus-nerve-belong-to-the-sensory-somatic-or-autonomic-system

Furthermore, the vagus nerve is also responsible for modulating the permeability of the intestinal barrier. Vagal innervation maintains the intestinal barrier by increasing the expression of occludin tight junction proteins. Vagal nerve stimulation has been shown to protect the gut barrier against LPS-induce permeability, and also prevents burn induced intestinal permeability.

Vagus intestinal permeability

Bonaz, Bruno et al. “The Vagus Nerve at the Interface of the Microbiota-Gut-Brain Axis” Frontiers in neuroscience vol. 12 49. 7 Feb. 2018, doi:10.3389/fnins.2018.00049

According to the authors of one paper:

Vagal activity provides a protective function to the intestinal epithelial barrier and a low vagal activity makes intestinal epithelium more permeable thus promoting systemic inflammation and chronic disease.

In other words, when the vagus nerve is not functioning correctly, intestinal permeability can be one of the symptoms. The importance of healthy vagus nerve function in healing leaky gut syndrome can therefore not be overstated.

The Thiamine Connection

Thiamine is essential for the function of the vagus nerve, in part due to its role in production of the neurotransmitter acetylcholine, which is the primary neurochemical used by the vagus nerve. Without enough thiamine, the vagus nerve cannot function in the normal way. For more information, read this article which looks at the connection between thiamine deficiency and small intestinal bacterial overgrowth: When Sibo & Ibs-Constipation Are Just Unrecognized Thiamine Deficiency

Thiamine also exerts direct effects on the intestinal barrier. Research suggests that a deficiency can lead to increase intestinal permeability and a greater tendency towards inflammation. Thiamine is necessary for maintaining intestinal epithelial cell bioenergetics, and reduced activity of thiamine-dependent enzymes may lead to a defective gut barrier. One rat study on the thiamine deficient gut showed a staggering 42-66% reduction of brush border enzymes. The same study found a 20% reduction in intestinal weight and a significant thinning of the microvillus membrane

Thiamine injected into acupoints successfully prevented intestinal permeability among colon cancer patients in one Chinese report. Thiamine also appears to have direct anti-inflammatory effects in the gut of ruminant animals, showing a reduction in intestinal permeability through enhanced production of barrier proteins, protection against bacterial lipopolysaccharide-induced inflammation, and improved barrier function.

In 2015, researchers in Japan discovered a novel role for thiamine in facilitating the protective action Secretory IgA against immune threats. Secretory IgA may prevent intestinal barrier dysfunction, possesses immunomodulatory properties and may play a role in inflammatory bowel diseases such as UC and Crohn’s. Atrophy and inflammation of mucosal surfaces in the gut have been documented as a result of experimental thiamine deficiency.

How to Heal Leaky Gut Syndrome Naturally

Diagnosis of Leaky Gut Syndrome can be difficult without specialized testing. However, if the underlying factors are addressed and a holistic healing approach is adopted, you can fix a leaky gut and restore your gut health. Let’s take a look at how to heal leaky gut syndrome naturally. Aside from thiamine, the following nutrients have been shown to exert positive effects on the intestinal barrier and can be extremely useful:

All of which are included in our brand new, upcoming formulas: BetterGut Essential, and BetterGut Plus

Other nutrients that can be useful include L-glutamine, vitamin A & vitamin D, and collagen peptides. Aside from supplements, here are a few other things which can also be implemented:

Other ways to improve Leaky Gut

Remove trigger foods and optimize the diet

Identify your trigger foods and eliminate them from your diet. These trigger foods may include items in your diet that may be causing inflammation or gut irritation. Typically refined sugars, processed foods, pasteurized dairy, and gluten fall under this category of foods.

Avoiding industrial vegetable/seed oils such as a canola, sunflower, cottonseed, soybean, grapeseed, rapeseed, mustard, and peanut should be top priority. Replace them with healthy fats such as butter, ghee, and beef/lamb tallow. Another important step is to reduce consumption of vegetables high in lectins and oxalates. Increasing the amount of fermented foods such as kefir, sauerkraut and kimchi can also be a useful tool to improve overall diversity of the microbiome.

Support your Digestion

Take digestive enzymes and supplements to help repair your intestinal lining and lend support to your digestive system. Digestive bitters (bitter herbs) prior to meals is advised.

Stress Management

Stress management creates a positive impact on your gut health as well as your overall well being. Practice techniques like yoga, deep breathing exercises, meditation, or any other physical activities that work for you.


Minimize your exposure to environmental toxins that may be triggering your gut health. Choose organic foods, clean & additive-free products, and filtered water to minimize your toxin ingestion.

We also recommend you watch this video by EONutrition, where he talks about how he fixed his gut after going through a series of long-term gut problems:



Healing a leaky gut requires a multifaceted approach that involves addressing the underlying factors, enhancing the gut health, and promoting your overall well-being. Implementing a gut-friendly diet, managing your stressors, and including nutritional supplements in your lifestyle can help you not only reclaim, but even improve your health. Gut healing and taking care of your gut is not just about lifestyle management, it plays an extremely important role for a healthy life span. So start making those changes in your lifestyle from today and transform your gut health for good!

*These statements have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure or prevent any disease.
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