What is Leaky Gut?

Dr. Jolene BrightenPublished: Last Reviewed: Thyroid & Hormone Balance Leave a Comment

Like the term adrenal fatigue, you may have heard the expression leaky gut floating around on the internet. In the same way that adrenal fatigue is not a medical term and more of a layman's term used by patients, neither is leaky gut. Instead, medical professionals refer to the phenomenon of “leaky gut” as intestinal hyperpermeability.

While your doctor may not believe leaky gut exists, there’s actually quite a bit of scientific evidence suggest it does and can cause a host of issues.

If you read my article, Why Adrenal Fatigue Isn’t Real, you’ll understand that it was my tongue-in-cheek way of saying that it’s okay to use non-medical terms when communicating with your doctor, friends, or family, but it is important to understand what exactly is going on. 

Here, we’ll go through everything you need to know about leaky gut – what it is, what causes it, symptoms, and how to heal it.

What Is Leaky Gut?

Intestinal hyperpermeability (or leaky gut syndrome) is a gastrointestinal condition that occurs when the tight junction between the cells of your intestinal lining (the seal between cells) is compromised, allowing larger food particles and microorganisms to “leak” through. 

This tight junction regulates what comes in and goes out of the intestinal wall. Under normal conditions, the intestinal wall creates a barrier protecting the body from harmful substances entering the bloodstream.

When pathogens, food particles, and other proteins enter through the intestinal wall it has the potential to activate the immune system and cause widespread inflammation.

Causes Of Leaky Gut

While some of us may have a genetic predisposition to a leaky gut, the way we live today (i.e., how we eat, our stress, how we take certain medications) is a huge factor in our gut health. In truth, the causes of leaky gut is still an area of research that we are learning more about.

Exposure to foods you are intolerant or allergic to, chronic stress, gut infections, NSAID, or antibiotic, oral contraceptive pills (the pill) use… all of these things may cause those spaces between the cells of your intestinal lining to break down. When this happens, larger protein molecules (like food, bacteria, yeast, etc.) may escape into the bloodstream.

Zonulin is a protein known to regulate intestinal permeability. The activation of zonulin from bacteria, gluten, and other sources can trigger leaky gut in those who are genetically susceptible.

It’s important to note that research has shown gluten to be a factor in intestinal hyperpermeability with celiac disease, but not gluten sensitivity.

The following are factors thought to play a role in the development of leaky gut:

  • Excessive Alcohol Use: Consuming large amounts of alcohol, also known as binge drinking, or chronic use may contribute to leaky gut.
  • High Sugar Consumption: A diet high in sugar can damage the tight junctions of the intestine.
  • High Stress Lifestyle: High stress levels can lead to an array of digestive issues, including leaky gut.
  • Non-Steroidal Anti-Inflammatory Drugs (NSAIDs): Chronic use of NSAIDS can lead to intestinal hyperpermeability.
  • Gut Dysbiosis: Your gut houses many different types of organisms, some of which can become problematic when they overgrow or are out of balance.
  • Yeast Overgrowth: Yeast is normally found in the gut, but when it overgrows it can contribute to leaky gut.
  • Nutrient Deficiencies: Zinc, vitamin A, and vitamin D are essential for intestinal wall integrity. When deficient in these nutrients there can be a higher risk of leaky gut.
  • Inflammation: Your gut houses the majority of your immune system. Chronic systemic inflammation can contribute to a breakdown in the intestinal barrier.
  • Oral Contraceptive Pills: The pill has been shown to alter intestinal permeability, which can make those with a genetic predisposition more susceptible to developing inflammatory bowel disease.

Leaky Gut Symptoms And Signs

When larger food particles (as opposed to food broken down into manageable molecules the body can use) make their way past the gut barrier, the body recognizes this as “non-self” and mounts an immune response to attack them. 

Leaky gut symptoms include:

Disease Associated with Leaky Gut

While there are many claims of leaky gut being at the root of chronic disease, not all of these are supported by the research. The following are diseases that have been demonstrated to be associated with leaky gut.

Food Allergies

There is a strong correlation between the presence of leaky gut and the development of food allergies. When larger food proteins are allowed to pass through the intestinal barrier the immune system is given an opportunity to mount a response. An IgE mediated immune response is the definition of a food allergy.

Crohn’s Disease

It’s well recognized that leaky gut plays a role in Crohn’s disease.

In one study both those with Crohn’s disease and unaffected family members gut integrity was assessed. What was found is that intestinal permeability may be a risk factor for developing Crohn’s disease rather than a result of the condition.

Irritable Bowel Syndrome (IBS)

IBS can be characterized by diarrhea, constipation, or alternating of both. Researchers have found a correlation between IBS and intestinal permeability

Atopy is when an individual is predisposed to asthma, allergies, and eczema. Studies have shown there may be a stronger correlation between IBS patients with eczema, asthma, or hayfever and small intestinal permeability when compared to those without atopy.

Diabetes Mellitus

In Type 1 diabetes it proposed that proteins escaping through the intestinal barrier leads to activation of the immune system and may be the trigger for autoimmunity that leads to the destruction of insulin producing beta islet cells.

In one study it was found that zonulin upregulation preceded the onset of Type 1 diabetes suggesting it is a factor that can contribute to the development of autoimmune diabetes. Animal studies have also suggested that leaky gut plays a role in the development of autoimmunity against the pancreas cells.

Other studies have looked at leaky gut as a therapeutic intervention for both Type 1 & 2 diabetes.

Celiac Disease

Celiac disease is an autoimmune condition in which gluten causes the immune system to mount an attack on the gut itself. Intestinal permeability is well recognized to play a pivotal role in celiac disease.

Autoimmune Disease

Autoimmune disease is a condition in which the immune system mistakenly attacks the tissue of the body. Autoimmunity can affect any system in the body and show up in a variety of ways.

As highlighted above, there are specific autoimmune conditions associated with leaky gut. Both clinical and rodent models have suggested that increased intestinal permeability play a role in the development and progression of autoimmune disease.

Environmental factors, genetic predisposition, and enhanced gut permeability have been proposed as a mechanism for the development of autoimmunity.

How To Test For Leaky Gut

If you looked at those symptoms of leaky gut and thought, wow, that sounds like me, it might be a good idea to contact your doctor and discuss testing.

A lactulose: mannitol test can be performed to determine if you have a leaky gut. After drinking a carbohydrate solution, you will perform a urine collection. Urine that contains high amounts of sugar is considered a positive for leaky gut. This test is considered a non-invasive assessment.

How To Heal Leaky Gut

Leaky gut is not an official medical diagnosis at this time and therefore, there isn’t a set treatment protocol. However, there are elements of supporting gut health that are well understood that I have successfully employed in my clinical practice.

Healing a leaky gut is not a quick process. It requires time, patience, and a lifestyle shift. What do I mean by a lifestyle shift? Well, it may surprise you to learn that lifestyle factors — aside from diet — may also help improve gut health. 

Exercise for Better Gut Health

Research has shown that exercise may increase the diversity of microflora (helpful bacteria) in the gut, which can help balance the beneficial vs. harmful bacteria that reside in the gut. 

Improve Sleep

Sleep is another lifestyle factor to consider when starting to manage leaky gut syndrome. We now know that bad sleep habits (as in, not getting enough sleep) can play a role in our overall health. A study of mice showed that a disturbed circadian rhythm (in simpler terms, the internal clock that governs when you’re awake and when you’re asleep) could affect the gut microbiome negatively. If you regularly pull all-nighters and don’t prioritize sleep, check out my article about the many reasons our bodies need sleep, as well as tips to improve your sleep hygiene. 

Reduce Stress 

As stress can have a detrimental effect on our gut health, managing it is key in healing your gut. 

Exercise has the benefit of improving gut health and reducing the effects of stress. In addition, you can try deep breathing practices, journaling, meditation, a gratitude practice, or other relaxation practices to help your body cope with stress.

You’ll find more stress reducing strategies in this article.

Limit or Eliminate NSAIDs

NSAIDs can be a common go to for period pain. Instead, try the therapies recommended in this article.

NSAIDs may be necessary, but whenever possible, try to take a different approach. A one time use isn't going to be detrimental to your gut health, but we do need to be aware of chronic NSAID use, especially because it can also impact our hormones and potentially our fertility.

Leaky Gut Diet And Supplements

The Standard American Diet (SAD) is notoriously low in fiber and high in sugar. A high-sugar, low-fiber diet does not create the ideal environment for helpful gut bacteria to thrive. Instead, it can lead to harmful gut organism overgrowth, which may eventually lead to a situation where there are more bad bacteria than good bacteria. This is called gut dysbiosis. 

Eating a nutrient-dense diet rich in high-quality protein, fat, and carbs is a great way to support your digestive system and nourish the good bacteria in your gut. Fiber-rich foods provide the body with vital nutrients, help you move waste out of the body, and support hormones — all of which help when trying to address a leaky gut. If you’re looking for a place to start, grab my free meal plan and recipe guide aimed at helping you heal your gut and hormones.

A good leaky gut diet plan is high in plants, nutrient dense foods, and low in alcohol and sugar.

It can be daunting to change the way we eat, especially if we’ve been eating a certain way for many years. So keep it simple. Slowly increase the amount of nutrient-dense food on your plate while decreasing the nutrient-poor food. Eventually, you will fill your plate with only foods that will fuel and nourish your body. 

Eating probiotic-rich foods, such as sauerkraut, beet kavvas, and kimchi. Additionally, high-quality bone broth (either bought from a trusted brand or homemade) is incredibly nourishing and helpful for those on a mission to improve their gut health. 

Sometimes, in addition to dietary improvements, supplementation might be necessary.

Supplements to Support Gut Health

  • Gut Rebuild. This supplement features ingredients like aloe vera extract, L-glutamine, and marshmallow root — all of which can help support better gut health. In addition, it has zinc L-carnosine, which is a form of zinc that has been specifically shown to support gut healing.
  • Digest. The importance of properly breaking down our food cannot be overstated. Unfortunately, many people have low stomach acid, and their bodies do not release enough digestive enzymes to effectively digest their food. Being able to effectively break down what we eat is a great way to help the gut.
  • Women's Probiotic. Women's Probiotic is a blend of five spore-form Bacillus strains specifically designed to support gut health and rebalance flora. Probiotics have been shown to benefit gut health, including leaky gut.

You’ll find these three supplements as part of our Gut Repair Kit.

In Summary

Leaky gut syndrome is a state of intestinal hyperpermeability that allows harmful organisms and large proteins to enter the bloodstream. This process may aggravate the immune system leading to a host of symptoms and potentially triggering autoimmunity.

While there are medical providers who deny the existence of leaky gut, there is a large body of evidence to not only suggest it exists, but that it can also impact your health.

To heal leaky gut and prevent it, eating a diet rich in fiber and nutrients, limiting NSAIDs, addressing stress, and eliminating any potential aggravating factors is essential.

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About The Author

Dr. Jolene Brighten

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Dr. Jolene Brighten, NMD, is a women’s hormone expert and prominent leader in women’s medicine. As a licensed naturopathic physician who is board certified in naturopathic endocrinology, she takes an integrative approach in her clinical practice. A fierce patient advocate and completely dedicated to uncovering the root cause of hormonal imbalances, Dr. Brighten empowers women worldwide to take control of their health and their hormones. She is the best selling author of Beyond the Pill and Healing Your Body Naturally After Childbirth. Dr. Brighten is an international speaker, clinical educator, medical advisor within the tech community, and considered a leading authority on women’s health. She is a member of the MindBodyGreen Collective and a faculty member for the American Academy of Anti Aging Medicine. Her work has been featured in the New York Post, Forbes, Cosmopolitan, Huffington Post, Bustle, The Guardian, Sports Illustrated, Elle, and ABC News. Read more about me here.