A leaky gut is characterized by perforations in the intestinal wall that allow molecules or microorganisms to pass through into the bloodstream. The phenomenon is a profound failure of the intestines’ duty to act as a protective barrier. Leaky gut syndrome is difficult to diagnose; many physicians do not know to look for it when diagnosing patients who are experiencing a complicated array of symptoms.
What Exactly Is the Gut?
The gut encompasses the intestinal mucosa (lining), the microbial community (and their genes) in the intestines, and the associated immune system and nerves connected to these organs. Despite being arguably the most important organ in the digestive system, the intestines are also the largest immune organ,  with roughly 2,700 square feet (or 250 meters) of surface area.  We’re constantly exposing this tennis court-sized area to the outside world when we eat or drink. The properly digested molecules (micro-, macro-, and phytonutrients) in our food are supposed to filter through the intestinal mucosa, which is made up the epithelial cells on the surface of the small intestine. All the undesirable things (like inflammatory, harmful substances or organisms, or undigested food) that you don’t want to get past your intestines (and into the bloodstream) is supposed to stay in the intestinal lumen to continue it’s journey to the colon for elimination.  But with a leaky gut, the contents of your intestine can slip, unregulated, between the epithelial cells of the intestine. 
The spaces between the intestinal cells, the tight junctions, are supposed to form a seal between the inside of the intestinal lumen and the inside of the body beyond the digestive tract. When the tight junctions aren’t tight enough, things that shouldn’t be in the body slip past your intestinal gatekeepers and into the bloodstream. From here pathogens, toxins, and antigens can circulate throughout the body, wreaking havoc as they go by provoking a systemic inflammatory response.  The loose gaps between the cells in the intestinal mucosa are associated with a myriad of conditions and syndromes including:
- Inflammatory bowel disease (IBD)
- Irritable bowel syndrome (IBS)
- Type 1 diabetes
- Rheumatoid arthritis (RA) 
- Food allergies
- Celiac disease 
- Asthma 
- Autism 
- Parkinson’s 
What Causes Leaky Gut?
Far from a perfect, secure barrier, your tight junctions actually relax and contract based on variety of factors. An imbalance in anything from your diet, hormones, neurotransmitters, inflammatory mediators, immune cell products, and pathogens can disrupt the proper functioning of your tight junctions. 
Few things affect your health as much as your diet. Several primary offenders appear to contribute to the development of leaky gut:
- Alcohol: When the human body metabolizes alcohol, the metabolic product acetaldehyde can increase intestinal permeability. 
- Sugar: Sugar and artificial sweeteners cause inflammation that compromises gut health. Additionally, a urine analysis that measures glucose in the urine is a useful indicator of the severity of leaky gut. 
- Dairy: Dairy products are linked to gastrointestinal disorders—particularly among autistic individuals. 
- Gluten: Consumption of gluten is associated with increased intestinal permeability in those with gluten sensitivity. 
- Additives: Industrial food additives such as emulsifiers, solvents, microbial transglutaminase, glucose, and salt are linked to leaky gut syndrome. 
- Pesticides: Glyphosate is linked to disturbances in gut bacteria, which can contribute to the development of intestinal permeability. 
Several species of candida are known to disrupt the makeup of a healthy gut microbiota. The resulting imbalance in the microbiota is called dysbiosis.  These disturbances can lead to the development of digestive disorders including leaky gut. 
3. Chronic Stress
It’s no secret that stress negatively affects your health   but it’s especially demanding on gut health. Psychological stress increases the presence of inflammatory cytokines, a class of signalling proteins created by the immune system, which contribute to the development of leaky gut. Animal studies have shown that both psychological and physical stress compromise the integrity of the intestinal barrier. 
4. Environmental Toxins
Our environment is flooded with harmful chemicals and substances, many of which pose a significant risk to your health. Mercury,  BPA,  fungicides, and insecticides  have all been linked to increased intestinal permeability.
Non-steroidal anti-inflammatory drugs (NSAIDs), such as aspirin, ibuprofen, and naproxen have also demonstrated a tendency to increase intestinal permeability and provoke inflammation. 
6. Zinc Deficiency
Zinc is an essential trace mineral that supports the immune system  and plays a significant role in irritable bowel diseases. Zinc deficiency can lead to intestinal permeability, while supplementation with zinc increases the function of the tight junctions. 
Symptoms of Leaky Gut Syndrome
It’s difficult to predict the total impact of a leaky gut on the body as a whole. However, there are numerous symptoms that may indicate intestinal permeability. Some of the more obvious consequences of leaky gut include allergies,  cardiovascular disturbances,  and a multitude of metabolic disruptions.    Chronic fatigue syndrome and depression are separate and unique conditions, but both are known to result from compromised integrity of the intestinal mucosa.  
Intestinal permeability allows foreign microbes access directly to the bloodstream. As a response, the immune system releases antibodies,  which mistakenly attach to normal proteins in the blood, tagging them for immune action. Fortunately, there are several things in your control to help ease the burden of living with a leaky gut.
What’s the Best Solution for Leaky Gut?
Following a healthy diet is one of the most effective ways to help manage leaky gut. Foods that are a source of probiotics are especially helpful for mitigating the effects of the disorder.  Nutrients like glutamine and curcumin can support the intestinal environment by reducing the overstimulated immune response and the resulting oxidative stress that contributes to the weakening of the intestinal wall. 
Monitoring what goes into your body is one of your best natural remedies for managing leaky gut. If you suffer from a digestive disorder, whether it’s leaky gut, irritable bowel syndrome, celiac disease, Crohn’s disease, or any one of the myriad of disorders associated with hyperpermeability, try keeping a daily food journal to help identify the foods that trigger symptoms. If you experience frequent flare-ups, it’s time to make significant lifestyle changes such as incorporating the best foods for leaky gut into your diet for your health and quality of life.
Do you have experience with a leaky gut? What insight can you offer? Leave a comment below and share your thoughts.
by Dr. Edward Group DC, NP, DACBN, DCBCN, DABFM
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