Leaky gut was found to be associated with many health problems, including chronic inflammation, pain, cognitive diseases, and autoimmune conditions. How do you know if you have leaky gut? There are several symptoms of leaky gut. In this article, I will be discussing the problems of leaky gut and how to identify if you have a ‘leaking intestines.’
Your intestines are designed to allow food particles to be digested, moved, and absorbed nutrients. It also functions as a barrier between about five to seven pounds of bacteria, chemicals, and undigested food and the rest of your body. Imagine a condition in which particles of undigested food or bacteria from your intestines can pass through or between your intestine cells into the bloodstream where it can cause damage and irritate your immune system. This condition is real and is called intestinal permeability or ‘Leaky Gut.’
Studies show that dysfunction of the gut is associated with several diseases, such as arthritis and joint pain. Children with idiopathic (unknown origin) arthritis who were taking NSAIDs (e.g. Ibuprofen or Aleve) found to have increased intestinal permeability together with digestion symptoms. (1) Furthermore, dysfunction of the gut, in form of intestinal permeability, was found to be associated with nerve damage, neurodegenerative diseases (such as Parkinson’s), (2) the development of autoimmune diseases, and tumors. (3)
The gastrointestinal tract has a single layer of cells that separates the inside of the body from the external environment, i.e. the food, bacteria, or toxins that are ingested. When we eat food, the stomach breaks down the food in both chemical (using acid and enzymes) and mechanical way. After a few hours, the partly digested and ‘mashed’ food is called ‘Chyme’ and is ready to be slowly released to the small intestine. Chyme, the half-digested food, travels through the small intestine, is slowly mixed with friendly bacteria, enzymes, bile from the gallbladder which assist with the breakdown and digestion of nutrients. The length of the small intestine can vary greatly, from as short as 2.75 m (9.0 ft) to as long as 10.49 m (34.4 ft).
The picture below shows a close-up of the small intestine with the food and bacteria. In between the cells, there are doors called ‘Tight-Junctions’ with a very important role of maintaining the undigested food, bacteria, toxins and other materials from passing through the cells into the bloodstream, where they can flow anywhere. On the bottom of the small-intestine picture, you can see what happens when the tight junctions are open: small particles, such as undigested food or bacteria can pass into your blood-stream.
What causes intestinal permeability or leaky gut? Zonulin, a molecule of protein, was found to regulate the tight junctions in the gut by opening and closing the spaces or "junctions" between cells in the lining of the digestive tract. Several factors stimulate the secretion of Zonulin, which increases leaky gut.
How Do You Know If You Have Leaky Gut?
As I mentioned before, leaky gut is a potentially harmful condition. There are several ways and symptoms to identify if you have leaky gut. Here are the main symptoms:
You have symptoms, such as skin problems after eating certain foods.
Have abdominal pain or irritable bowel syndrome
Felt brain fog or a change in mood after eating certain foods, such as gluten
Have food sensitivity or allergy
Feel mood changes, decrease memory, or ‘brain fog’ after eating certain foods
Suffer from allergies or chronic sinus congestion
Have or had unexplained infections
Have chronic inflammation with joint pain
Feeling low energy or chronic fatigue all the time
How to Test for Gut Permeability
There are several ways to measure gut permeability or ‘leaky gut,’ The simplest way to test gut permeability is through a test called ‘Intestinal Permeability Assessment.’ This test measures the ability of two large sugar molecules to pass through the intestinal lining. The patient drinks lactulose and mannitol and the lab measure the levels of the two sugars recovered in a urine sample. If they are found in urine, it indicates that they ‘leaked’ through the gut. This is a simple and reliable test. (4)
The picture below shows sample results of a patient who was tested and diagnosed with leaky gut.
Lactulose is a large sugar molecule that is poorly absorbed in our gut. A large amount of lactulose in this sample indicated that it was ‘leaking’ through the intestinal cells into the bloodstream. This indicates a state of ‘leaky gut.’
Mannitol, another molecule of sugar is absorbed through the intestinal cells and serve as a marker for intestinal absorption. Lower than normal levels might indicate poor absorption of nutrients.
If the ration is too high between both molecules, it also indicates leaky gut.
What Causes Leaky Gut?
A large portion of your immune system is located in your gut, therefore, any chronic inflammation in your gut might lead to dysfunction of the tight junctions and ‘leaky gut.’ According to accumulating studies, ‘leaky gut’ is caused by:
Celiac disease (CD) (5)
Chronic stress in adults was found to cause a change in the intestinal bacteria, an increase in interleukin 6 (IL-6) activity, increase leaky gut. (6, 7)
Consumption of Nonsteroidal anti-inflammatory drugs (NSAIDs), such as Ibuprofen, Aleve, and naproxen can lead to loss of the intestinal integrity. (8)
Consumption of gluten might lead to Zonulin secretion, inflammation, and damage to intestinal epithelial. (9)
Use of antibiotics, which reduces the amount (and type) of friendly and protective bacteria. (10)
Chronic exposure to mercury from fish or seafood even in concentrations similar to those found in food (11)
Exposure to pesticides by consuming non-organic food. Studies found that consumption of chlorpyrifos, a pesticide that is aimed to kill worms and insects, leads to increased permeability (‘leaky gut’). (12) This toxin results in more than 10,000 human deaths a year. (13)
Harmful bacteria in your gut. Studies show that harmful bacteria secretes toxins that can damage your intestinal mucus layer, a protective layer over your gut lining. (14)
Chemotherapy, which damages the gut. (15)
Yeast infection. Candida usually causes inflammation and elevation of pro-inflammatory cytokine IL-17. (16)
Chronic consumption of alcohol, which is known to damage the intestine.
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Uhde M, Ajamian M, Caio G, et al Intestinal cell damage and systemic immune activation in individuals reporting sensitivity to wheat in the absence of coeliac disease Gut Published Online First: 25 July 2016. doi: 10.1136/gutjnl-2016-311964
Tulstrup MV-L, Christensen EG, Carvalho V, et al. Antibiotic Treatment Affects Intestinal Permeability and Gut Microbial Composition in Wistar Rats Dependent on Antibiotic Class. Loh G, ed. PLoS ONE. 2015;10(12):e0144854. doi:10.1371/journal.pone.0144854.
Guichard A, Moreno BC, Aguilar B, et al. Cholera toxin disrupts barrier function by inhibiting exocyst-mediated trafficking of host proteins to intestinal cell junctions. Cell host & microbe. 2013;14(3):294-305. doi:10.1016/j.chom.2013.08.001.
Joly Condette C, Khorsi-Cauet H, Morlière P, et al. Increased Gut Permeability and Bacterial Translocation after Chronic Chlorpyrifos Exposure in Rats. Blachier F, ed. PLoS ONE. 2014;9(7):e102217. doi:10.1371/journal.pone.0102217.
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