Leaky gut, also called increased intestinal permeability, is currently gaining increasing attention in scientific literature and the media because of its proposed associations with numerous health conditions.
In a normal healthy gut, the inner lining of the intestinal wall is a closed barrier that selectively allows water and nutrients to cross into the bloodstream and prevents unwanted particles such as food, toxins, bacteria, and viruses from entering the bloodstream.
When increased intestinal permeability, or leaky gut, is present, the inner lining of the intestinal wall becomes damaged and “leaky.” This allows for larger unwanted particles to cross into the bloodstream. The unwanted particles in the bloodstream are then able to travel and cause inflammation in other areas of the body.
A leaky gut has been associated with many chronic inflammatory health conditions like Celiac disease, Crohn’s disease, autoimmune disorders, neurological disorders, and mood disorders. Like many things in functional medicine, a leaky gut is often a symptom of an underlying root problem.
It’s important to note that leaky gut syndrome is not currently recognized as a conventional medical diagnosis. On the other hand, functional medicine commonly diagnoses this syndrome through a comprehensive questionnaire and specialty lab testing.
What Causes Leaky Gut
There are many potential root causes of leaky gut, and it’s challenging to have an all-encompassing list. These are some of the most common, well-studied root causes.
Pharmaceutical medications can have more than one effect on the body. Several drugs can directly affect the GI system, causing gut inflammation and damage to the cells lining the gut wall.
One of the most common offenders is NSAIDs, like ibuprofen. NSAIDs directly disrupt the lining of the gut, causing increased permeability. NSAIDs also increase the risk of stomach ulcers and bleeding from these medications. These effects can occur within 24 hours of taking a dose and are more common in people with inflammatory conditions taking large and frequent doses of NSAIDs.
Chemotherapy and radiation are developed to target rapidly growing cells like cancer cells. The Gut, however, is also made of rapidly growing cells and regenerates every three to four days making it the perfect target for chemotherapy. This effect has been termed “chemo-gut.”
Food sensitivities are extremely common and are on the rise. Recent studies show that our Standard American Diet and lifestyle can negatively affect the gut microbiome, causing inflammation and lower immunity.
Eight common foods account for about 90% of all food allergies. Those same foods are often the source of intolerance in people who aren’t allergic to them but still have a sensitivity.
Gluten especially is linked to increased intestinal permeability and has been long studied in inflammatory bowel diseases such as Celiac and Crohn’s disease.
Stress has become ubiquitous, and not all stress is bad. However, studies have demonstrated a causative relationship between stress leading to increased intestinal permeability. Constant high levels of stress lead to chronically elevated cortisol levels and a weakening of the immune system—the inflammation in the gut results in leaks in the cell membrane of the gut.
The Standard American Diet (SAD) contains highly inflammatory and processed foods. For example, Fructose, a sugar commonly found in highly processed foods, has been shown directly to increase intestinal permeability. Other highly processed foods, such as refined seed oils, gluten, processed meats, dairy, artificial sweeteners, and alcohol, cause inflammation and damage to the gut lining, leading to a leaky gut.
Alcohol is commonly consumed worldwide. While red wine has shown some health benefits due to polyphenols, excess alcohol intake has been shown to have harmful health effects. Excess Alcohol intake alters the normal beneficial gut bacteria and causes intestinal inflammation. This combination of dysbiosis and inflammation can contribute to a permeable gut lining.
Toxin Exposure and Toxic Overload
We are constantly bombarded with toxic chemicals every day in our environment. These chemicals alter the hormonal balance in our body, degrade the lining of our gut, and can lead to gut microbiome imbalances.
Glyphosate, the most common pesticide also known as “Roundup,” has been shown to disrupt the normal beneficial gut bacteria and directly cause gut dysbiosis, leading to a leaky gut.
Low Stomach Acid
The gastrointestinal system starts in the mouth and travels throughout the body. There are many hormones and enzymes produced along the way that aid in digestion and nutrient absorption. Stomach acid plays a crucial role in digestion and immune function. When stomach acid production is reduced, commonly due to high stress and a high cortisol state, this can lead to increased inflammation, a weakened immune system, and nutrient deficiencies, all resulting in intestinal permeability and leaky gut.
Several studies have demonstrated that nutrients play essential roles in maintaining a healthy intestinal epithelium. In studies, Vitamin A or Vitamin D deficiencies showed an increase in gut inflammation leading to increased intestinal permeability.
Leaky Gut Signs & Symptoms
More recognizable signs and symptoms of leaky gut are gastrointestinal. Gastrointestinal symptoms may be:
- Gas and bloating
- Changes in bowel patterns - diarrhea, constipation, or both
- Food intolerance or sensitivities
Symptoms of Leaky Gut can also be more nonspecific and general and thus more difficult to attribute until after the fact. More general symptoms may be:
- Brain fog
- Mood imbalances like depression, anxiety, ADD / ADHD
- Fatigue / low energy
- Chronic inflammatory disorders,
- Skin issues like eczema, acne, or rosacea
- Arthritis or joint pain
- Nutrient deficiencies
Other Disorders Associated With Leaky Gut
Many chronic conditions have been associated with Leaky Gut and resolved by healing the gut.
- Inflammatory bowel diseases like - Celiac and Crohn’s disease
- Rheumatoid arthritis
- Alzheimer’s disease
- ADHD / ADD
- Depression / Anxiety
Functional Medicine Labs to Rule out Leaky Gut
Functional Medicine laboratory testing is the cornerstone to determining the root cause of Leaky Gut. Conventional lab testing often comes back “within normal limits” but may not be at the optimal functional level that the body needs to thrive.
Food Sensitivity Testing
Food sensitivity testing is essential to determine if there is an underlying food sensitivity or intolerance driving inflammation in the gut. These tests not only test for foods but also for chemicals, artificial flavors, sweeteners, preservatives, food dyes, and additives in food that a patient may be reacting too.
Comprehensive Stool Testing with Zonulin
Gut microbiome testing with Zonulin level. Higher Zonulin levels are associated with increased intestinal permeability. Gut microbiome testing can help determine if there is an imbalance in the gut bacteria or the presence of parasite or bacteria overgrowth.
Hormone testing with a cortisol map helps identify hormonal imbalances, particularly cortisol imbalances related to chronic stress.
Nutrient testing is key to identifying a vitamin or nutrient deficiency. In particular, vitamin D levels are essential to optimize for overall healing.
Heavy metal and mold testing can help determine if toxicity is present in the environment.
How to Heal Leaky Gut
Finding the root cause of the leaky gut is the first step in treating it. This can be achieved with targeted functional medicine testing and a careful examination of the potential root causes. The 5 R program is used to help reduce triggers or offending agents to rebalance and heal the body.
Leaky Gut Diet (5 R Approach)
The 5 R approach is used to help heal the gut. It encompasses the 5 “R”s of gut-healing - Remove, Replace, Reinoculate, Repair, and Rebalance. Keep in mind that this process usually takes weeks or months to achieve.
Step 1 is Remove
Remove any offending foods, toxins, environmental stressors, and chronic stress. Food sensitivity testing, mold, heavy metal testing, and hormone testing can help identify any specific foods, toxins, or stressors for the body. Gluten, dairy, soy, eggs, sugars, caffeine, and alcohol are the most common food sensitivities.
It is generally advised to remove sensitive foods for 3 to 6 months before reintroducing them into the diet. Detecting any environmental toxin or stressor and eliminating them can help remove the overall inflammatory burden of the body.
If an offending pathogen is detected from a comprehensive gut test, your practitioner will work with you to develop a treatment plan. Targeting pathogens may involve treatment with pharmaceutical medication, antibiotics, or antimicrobial herbal supplements.
Step 2 is Replace
Replace nutrients and enzymes based on lab results.
Step 3 is Reinoculate
In functional medicine, we take a food-first approach. This means changing your diet to support a healthy gut microbiome. A diet rich in prebiotics, fiber, and fermented foods helps to support a healthy gut microbiome. Gut microbiome testing helps determine which strains of prebiotics and probiotics are best for each person.
Step 4 is Repair
Repairing damage to the gut lining takes time and doesn’t happen overnight. In the short term, supplementation can support the healing process. This is achieved in the long term by removing toxins and inflammatory foods and providing proper nutrients to the body through a healthy diet and lifestyle.
Step 5 is Rebalance
Rebalance the body. This includes mind, body, sleep, and nutrition. Ultimately, this is going to heal the gut for good and prevent leaky gut from occurring again in the future.
Herbs & Supplements for Leaky Gut
While lifestyle and dietary changes are essential for prolonged healing, supplements can be used during the repair phase to support the healing process. Many of these come in combination products for gut support.
Vitamin A & D are essential for proper gut function. Checking these vitamin levels and making sure they are optimized can help reduce inflammation.
Zinc is essential for overall wound healing in the body.
The amino acids Glutamine and Arginine have been studied, and supplementation has been supported to be anti-inflammatory and help heal the gut lining.
Fiber and prebiotics and probiotics help support a healthy and diverse gut microbiome.
Potent antioxidant and anti-inflammatory supplements like omega 3 fatty acids and curcumin reduce inflammation in the body and the gut.
Butyrate has been shown to help improve gut cell synthesis, and Inulin has also been shown to help heal the gut lining.
Supplemental digestive enzymes such as protease, amylase, lipase, and hydrochloric acid can help digestion and ease the digestive processes while healing.
Herbs like licorice root, aloe vera, and slippery elm have been shown to reduce inflammation and aid in healing the gut lining.
Lifestyle Changes to Address Leaky Gut
Lifestyle matters most when it comes to leaky gut, as it is a lifestyle that is most often the root cause of symptoms. Dietary changes are often necessary to decrease triggers of inflammation in the gut. Prioritizing sleep, exercise, and stress management are vital in allowing the body to heal itself.
A leaky gut is a common path and symptom of chronic inflammatory disease. There are many potential underlying root causes for leaky gut. While it may seem overwhelming or confusing to figure out what may be causing your leaky gut symptoms, you don’t have to go it alone, and you don’t have to guess. By working with an Integrative or Functional Medicine health practitioner, you can determine the underlying cause of your leaky gut and develop a personalized treatment plan to resolve the symptoms. The best news is that the body knows how to heal itself. Sometimes we just have to give it the tools it needs to help it along the way.
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