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Leaky Gut Syndrome: 7 Signs You May Have It

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Leaky gut - Dr. Axe

If you’ve been around the natural health world very long, you’ve probably heard of a condition known as leaky gut syndrome. It sounds pretty gross, but it’s an important enough problem to consider. There are several leaky gut symptoms to be aware of, which is particularly important since leaky gut is associated with dozens of related conditions and diseases.

As more Americans are affected by poor diet choices, chronic stress, toxic overload and bacterial imbalance, it appears that the prevalence of leaky gut has reached epidemic proportions. The medical profession is just now agreeing this condition may even exist, which is especially shocking to me because “intestinal permeability” (another name for leaky gut) has been discussed in the medical literature for over 100 years!

Why should leaky gut syndrome concern you? Recently leaky gut has been called a “danger signal for autoimmune disease.” (1) If you’re wondering if you may be experiencing leaky gut, the first thing to do is access your symptoms. Keep in mind that it’s very common for people on a Standard American Diet to struggle with poor gut function and high levels of inflammation — but just because digestive issues and autoimmune conditions are common doesn’t make them “normal”!

In this article, I’ve outlined a brief description of common leaky gut syndrome seen in people struggling with this condition. Can you heal leaky gut syndrome? As you’ll learn about below, there are four steps I recommend taking in order to repair leaky gut, which includes removing trigger foods from your diet, taking beneficial supplements and rebalancing your microflora with probiotics.


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 onto 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 our 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 “intestinal hyperpermeability.”

What Causes Leaky Gut?

The intestines are protected by a single layer of specialized epithelial cells that are linked together by tight junction (or TJ) proteins. Leaky gut symptoms are a consequence of intestinal tight-junction malfunction.

These tight junctions 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. Tight junctions 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 compounds from your diet or lifestyle) from passing out of your digestive system into the rest of your body. (1)

Here’s how a report published in the journal Frontiers in Immunology describes the pathology of leaky gut: (2)

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.’

When you have leaky gut, certain tiny particles that should never be able to enter your bloodstream start to make their way through. There’s also commonly 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.

The result? 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 leaky gut 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 un-sprouted grains, added sugar, GMOs, refined oils, synthetic food additives and conventional dairy products.
  • Chronic stress
  • Toxin overload — including 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.

How Serious Is Leaky Gut Syndrome?

Well, according to a 2014 review of the facts and research about intestinal permeability (among other sources), the chronic condition of hyperpermeability is linked to numerous symptoms and health conditions.

What are the symptoms of leaky gut? Some of the most prominent signs you may have leaky gut include: (3)

  • Gastric ulcers
  • Infectious diarrhea
  • Irritable Bowel Syndrome (IBS)
  • Inflammatory bowel diseases (Crohn’s, ulcerative colitis)
  • Small Intestine Bacterial Overgrowth (SIBO)
  • Celiac disease
  • Esophageal and colorectal cancer
  • Allergies
  • Respiratory infections
  • Acute inflammation conditions (sepsis, SIRS, multiple organ failure)
  • Chronic inflammatory conditions (such as arthritis)
  • Thyroid disorders
  • Obesity-related metabolic diseases (fatty liver, Type II diabetes, heart disease)
  • Autoimmune disease (lupus, multiple sclerosis, Type I diabetes, Hashimoto’s, and more) (4)
  • Parkinson’s disease (5)
  • Chronic fatigue syndrome (6)
  • Propensity towards weight gain or obesity (7)

While these diseases are linked to leaky gut syndrome, it hasn’t been proven that there is a causal relationship; in other words, it’s not yet established that leaky gut causes any of these conditions, just that people who have leaky gut are more likely to have a number of other health problems. So while the scientific evidence has not yet proven that intestinal hyperpermiability (leaky gut syndrome) is actually responsible for these conditions, it strongly suggests that leaky gut and other dysfunctions tend to occur simultaneously. (8)


7 Leaky Gut Symptoms and Signs

How do you know if you have leaky gut? Below you’ll find seven leaky gut symptoms and early occurring conditions that may point to an issue with your gut health.

1. Food Sensitivities

Because of the onslaught of toxins that enter the bloodstream, the immune systems of people with intestinal hyperpermeability are on overdrive mass-producing various antibodies, which may make their bodies more susceptible to antigens in certain foods (especially gluten and dairy). In studies involving rats and human children, leaky gut and food allergies have been linked. (910) Allergies are believed to be one of the most common leaky gut symptoms.

2. Inflammatory Bowel Disease 

Researchers from Hungary uncovered in 2012 that elevated gut permeability is oftentimes localized to the colon in people suffering from irritable bowel syndrome and ulcerative colitis. (11) As far back as 1988, scientists suggested that Crohn’s disease may be more of a risk for people with leaky gut. (12)

A small study (observing 12 patients) discovered that zinc supplementation may help resolve the tight junction dysfunction in these cases, although more research is required on a larger scale to confirm these results. (13)

3. Autoimmune Disease

The key to understanding how leaky gut can cause an autoimmune disease is through the research done on a protein known as “zonulin.” According to a 2011 article published in the journal Physiologic Reviews: (14)

Zonulin is the only physiological modulator of intercellular tight junctions described so far that is involved in trafficking of macromolecules and, therefore, in tolerance/immune response balance. When the finely tuned zonulin pathway is deregulated in genetically susceptible individuals, both intestinal and extraintestinal autoimmune, inflammatory, and neoplastic disorders can occur.

Eating gluten may trigger this dangerous cascade. University of Maryland School of Medicine researchers have uncovered that gluten “activates zonulin signaling irrespective of the genetic expression of autoimmunity, leading to increased intestinal permeability to macromolecules.” (15)

The good news is that, at least as far as leaky gut plays a role in autoimmune conditions, it is reversible and could potentially alleviate some of these problematic immune responses. (16)

4. Thyroid Problems 

One of the autoimmune diseases that leaky gut syndrome may directly affect is Hashimoto’s disease. (17) Also known as “chronic thyroiditis,” this disorder is displayed with hypothyroidism (low thyroid function), impaired metabolism, fatigue, depression, weight gain and a host of other concerns.

5. Nutrient Malabsorption

In my own patients, I’ve observed various nutritional deficiencies resulting from leaky gut, including vitamin B12, magnesium and digestive enzymes. Those common nutrient deficiencies are one reason why many functional medicine practitioners prescribe a whole-food multivitamin in addition to probiotics for people suffering leaky gut problems.

6. Inflammatory Skin Conditions 

First described over 70 years ago, the gut-skin connection theory has described how intestinal hyperpermeability can cause a slew of skin conditions, particularly acne and psoriasis. (18) Creams and drugs with endless lists of (sometimes dangerous) side effects are often prescribed for these skin disorders, yet there has been evidence for several decades that part of the root cause might exist in the gut.

7. Mood Issues and Autism

According to a study published in the journal Neuroendocrinology Letters, leaky gut has been shown to cause various neurocognitive disorders. For example, the inflammatory response characteristic of intestinal hyperpermeability triggers the release of pro-inflammatory cytokines and other chemicals that are thought to induce depression. (19)

A study published in the journal Nutritional Neuroscience described the “vicious circle between immune system impairment and increasing dysbiosis that leads to leaky gut and neurochemical compounds and/or neurotoxic xenobiotics production and absorption.”

The authors go on to describe findings from a number of studies that point to their theory that autism may be connected to problems in the gut microbiome, particularly within the first year of life. (20) It is actually a common hypothesis in modern science that leaky gut is strongly related to autism. (21)


What the Medical Community Has to Say About Leaky Gut Syndrome

Do most conventional doctors support the idea that leaky gut is real?

WebMD refers to leaky gut as “something of a medical mystery.” (22) This isn’t surprising, since it’s not a diagnosis that most doctors have been taught in medical school. “From an MD’s standpoint, it’s a very gray area,” says gastroenterologist Donald Kirby, MD – Director of the Center for Human Nutrition at the Cleveland Clinic. In his opinion, “Physicians don’t know enough about the gut, which is our biggest immune system organ.” (21)

To make matters worse, government agencies have also contributed to the confusion. According to the United Kingdom’s National Health Service (NHS), “There is currently little evidence to support the theory that a porous bowel is the direct cause of any significant, widespread problems.” (23)

Yet, not everyone agrees. A roundtable review quotes the researchers at seven different European universities in 2014 agreeing upon the following: (24)

Alteration of the gut barrier seems to have multiple consequences facilitating the onset of a variety of diseases depending on other hits and on genetic or epigenetic constellations, respectively. The growing significance of the gut barrier and bacterial translocation raises the questions of how we can improve gut barrier functions and gut microbiota.

So while it’s encouraging that science is coming around to leaky gut syndrome being a real problem, we are by no means at a point where there are standard diagnostic tools for testing and treating leaky gut.

In the Western/conventional medical world, if there are no standard diagnostic criteria for a disease, then there are no specific therapies or treatments available. Moreover, if there are no “proven” treatment models, then most MD’s are left with no other choice than to follow what they believe to be the “safe path” and prescribe drugs that only treat leaky gut symptoms. For example, medications (like proton pump inhibitors or antacids) can be used to manage symptoms like acid reflux medications but these drugs don’t solve the root problem.

Because much of the medical community denies leaky gut’s very existence, it’s critical that you understand what leaky gut is and what to look out for in case you or a loved one is affected by it. The good news is that many functional and integrative medicine practitioners have a greater understanding of this condition than they did even a decade ago. They are much more likely to help you determine if you are suffering from leaky gut syndrome and to give you tools to help repair your gut.


How Do You Get Rid of Leaky Gut?

Now that we’ve been talked about leaky gut symptoms, causes and opinions, let’s talk about how to test for and repair leaky gut.

How do you test for leaky gut?

Several leaky gut syndrome tests are available that can help confirm a diagnosis and point you in the right treatment direction. Tests are helpful for identifying specific sensitivities and uncovering which types of toxins or deficiencies are contributing to your symptoms. Leaky gut tests include:

  • Zonulin or Lactulose Tests
  • IgG Food Intolerance Test
  • Stools Tests
  • Organic Acid Vitamin and Mineral Deficiencies Tests
  • Lactulose Mannitol Test

What leaky gut treatments are available?

After years of research and patient care, I developed a four-step process for helping to heal leaky gut. I cover this process in my article entitled the Leaky Gut Diet and Treatment Plan. If you’re concerned that you or a loved one may have leaky gut symptoms, I encourage you to read the detailed instructions, food suggestions and recommended leaky gut supplements listed in this article.

The basic steps to healing leaky gut are as follows:

  1. REMOVE foods and factors that damage the gut.
  2. REPLACE these with healing foods as you follow an anti-inflammatory leaky gut diet.
  3. REPAIR the gut with specific leaky gut supplements like butyric acid.
  4. REBALANCE your microbiome with probiotics (beneficial bacteria). This is key because bacteria in your gut are a major component of the intestinal barrier. They help promote resistance to the colonization of harmful or pathogenic bacteria species by competing for nutrients. Gut microbiota also regulate the digestion and absorption of nutrients and help supply epithelial cells with energy.
Two of the most commons questions people ask are: “What can I eat if I have leaky gut syndrome? And what should I NOT eat when I have leaky gut?”
If you’re struggling with leaky gut or other GI issues, remove processed foods — including un-sprouted grains, added sugar, GMO’s, refined oils, synthetic additives and conventional dairy products. A healing leaky gut syndrome diet includes foods like:
  • Bone broth
  • Raw cultured dairy (like kefir, yogurt, amasai, butter and raw cheeses)
  • Fermented vegetables and other probiotics foods. Probiotics may help reverse leaky gut by enhancing the production of tight junction proteins that defend against intestinal permeability.
  • Coconut products
  • Sprouted seeds (like chia seeds, flaxseeds and hemp seeds)
  • Foods with omega-3 fatty acids, especially salmon and other wild-caught fish
  • Herbs and spices
  • Other nutrient-dense, anti-inflammatory foods like grass-fed beef, lamb, other fresh veggies and most fruits, apple cider vinegar, sea veggies, and other superfoods

Final Thoughts on Leaky Gut Syndrome

  • Leaky gut syndrome is classified by malfunction in the intestinal tight junctions in the digestive tract, allowing larger-than-usual particles to pass from the digestive system into the bloodstream. When this occurs, the balance of inflammatory immune responses is disrupted, leading to chronic inflammation and poor immunity.
  • Although no causal relationships have yet been officially established, leaky gut is correlated with a large number of issues and diseases, including digestive disorders, depression, autism, celiac disease, autoimmune disease and more.
  • Common leaky gut symptoms include: food sensitivities, digestive issues, autoimmune disease, thyroid dysfunction, nutrient malabsorption, inflammatory skin conditions and brain-related issues such as depression and autism.
  • Leaky gut syndrome is not a recognized diagnosis in the medical community yet — but I’m confident it will be recognized someday, due to the vast body of research that has already been conducted.
  • If you suffer from any leaky gut symptoms, I encourage you to consult with your naturopathic doctor about options for treatment. Many of my patients have seen improvements when adjusting to a healing diet, rather than a disease and inflammation-causing one. In addition, there are helpful dietary supplements many people implement to support better gut health.

Read Next: How I Bounced Back from the Silent Gut Condition


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