Have you ever heard
of the term "leaky gut" or "leaky gut syndrome"? Lots of
people have because it's so popular on social media sites like Pinterest and so
on. Well, this post will tell you what leaky gut is, what causes a leaky gut, the
symptoms of a leaky gut and how to heal and prevent a leaky gut.
What is leaky gut?
To have
a better understanding of what leaky gut is let's firstly look at the anatomy
of the digestive system from the stomach to the large intestine, secondly the
normal digestion or passage of food from the stomach to the large intestine of
someone without leaky gut and then thirdly of someone with leaky gut.
The anatomy of the digestive system from the
stomach to the large intestine and normal digestion or passage of food
The stomach is
followed by the small intestine and then the large intestine. The small
intestine is connected to the stomach on one end and the large intestine on the
other end. It is comprised of three sections.
Food leaves the
stomach and enters the small intestine. This is where nutrient absorption takes
place.
The gut (lumen) is
lined with intestinal epithelial cells aka intestinal epithelial lining (or
simply the lining of the gut). The intestinal epithelial cells are connected by
tight junctions and the tight junctions seal the epithelial cells. This lining is
responsible for digestion, nutrient and water absorption and it forms a
physical barrier against contents (food and microbes) in the lumen. After
nutrient absorption food leaves the small intestine and enters the large
intestine.
Someone with the leaky gut syndrome
When you hear the
words leaky and gut what comes to mind? For me, a gut that leaks.
Food will also leave
the stomach and enter the small intestine but this is where the problem exists.
A person with leaky gut will have a porous gut/small intestine which means that
their epithelial lining is compromised and as a result contents from the lumen
will enter the bloodstream thus creating a leaky gut. If the gut was not
damaged then it would have created a barrier that controls what is absorbed
into the bloodstream and what enters the large intestine as already mentioned
above.
So it can be concluded that the
intestinal epithelial lining forms a barrier that separates the host from the
environment or the outside world from the internal world.
And the definition
of leaky gut:
Leaky gut is when the lining
that lines our small intestine is damaged and foreign substances (undigested
food particles, waste products, bacteria, and toxins) escapes into the bloodstream.
More on the
intestinal epithelial lining, like what is it made up of?
The gut barrier is made up of an epithelial layer and a mucus
layer.
The intestinal
epithelial lining is made up of a single
layer of specialized epithelial cells that are linked together by tight
junction (TJ) proteins plus other factors. Cytokines, mucins, immunoglobulins
and antimicrobial molecules are those factors and they also support the gut
barrier. The intestinal permeability can increase if any abnormalities occur
among these factors.
As stated above,
increase gut permeability occurs when the gut barrier function is disrupted
which leads to a leaky gut and that causes inflammation to arise which can
result in autoimmune disease and so on.
Why?
80 percent of our
immune system is located within the gut wall. So when foreign substances enter the bloodstream, inflammation will arise. As these foreign substances
continuously pass into the bloodstream then this will cause the immune
system to continuously produce inflammation which will lead to chronic
inflammation which can lead to a whole bunch of illnesses (more on these further
down below).
What causes a leaky gut?
A leaky gut can develop as a result of:
What causes a leaky gut?
A leaky gut can develop as a result of:
- Gut flora imbalance /gut dysbiosis
About 100 trillion organisms typically comprise the gut microbiota (1). Good and bad microbes both make up the gut microbiota and a balance between these organisms is necessary for good health. The diversity of the microorganisms that make up the gut microbiota can change (or simply the balance is disrupted) and this change is referred to as gut dysbiosis. Additionally, a change in their diversity (a result of antibiotics, stress, diet, etc.) can make them become harmful to us (2). One such harm is that it can lead to a leaky gut (3).
How and how does it lead to leaky gut?
When an imbalance of the gut microbiota (gut dysbiosis) occurs and let us say a good species of microbes is killed off then pathogenic microbes can thrive. These pathogenic microbes will damage the gut barrier function and a damaged gut barrier function will lead to leaky gut.
It is important to note that certain microbes are not harmful in small numbers but they can become harmful in large numbers e.g. C. difficile.
An example of the importance of the balance of microbes in the gut microbiota:
Thick mucus coats the intestinal epithelium. This mucus is synthesized by goblet cells and forms a protective barrier against microorganisms. As already stated above, for good health, a certain balance within the organisms that make up the gut microbiota must exist. Wrzosek et al. (2013) studied the influence of Bacteroides thetaiotaomicron and Faecalibacterium prausnitzii which are two commensal bacteria on the mucus layer of the gut. Their study showed that the balance between these two bacteria is very important in maintaining colonic epithelial homeostasis because of each of their effects on mucus (4).
Causes of gut dysbiosis
- Diet (gluten)
- Antibiotic use
- Stress
More on these below.
What happens as a result of gut dysbiosis?
- Gut dysbiosis and IBD and CD.
The data from this study showed that dysbiosis (changes in the Firmicutes and Proteobacteria phyla) are associated with IBD and iCD (Ileal Crohn's disease) (5).
- Gut dysbiosis can cause a variety of very different diseases. Some of these diseases are Inflammatory bowel disease (IBD), Irritable bowel syndrome (IBS), Obesity, Celiac disease, Systemic lupus erythematosus (SLE), Rheumatoid arthritis (RA), Type-1 diabetes, Hypertension, Atherosclerosis, Atopic disease (e,g, childhood allergic asthma) and Clostridium difficile infection (CDI) (6).
2. Medications
We all take medications and certain medications can lead to a leaky gut. Some are:
- Non-steroidal anti-inflammatory drugs (NSAIDs) - e.g. Advil, Ibuprofen, Motrin and Aspirin
- Antibiotics
- Steroids (prednisone)
- Birth control (Oral Contraceptives)
Antibiotics Use
As already mentioned above, trillions of microbes make up the human microbiome and these microbes play important roles in our health. When we take antibiotics to treat certain conditions (such as bacterial infections) these antibiotics will kill and prevent the growth of beneficial microbes thus changing our microbiota (7).
It is important to note that the intestinal microbiota is necessary for the defense against pathogens and that colonization resistance and the production of antimicrobial compounds are the ways in which they achieve this. And so this negative change can consequently promote the growth of pathogenic microbes (If good microorganisms are killed off, the bad ones will flourish such as Candida) and it can affect us with this increase (which will cause inflammation). They are also involved in the development of the intestinal barrier.
An example, the microorganism, Clostridium difficile
This microbe (pathogen) is present in the gut but doesn't cause any disease in normal conditions (when it occurs in a small number). When we take antibiotics they will destroy the good microorganisms and so C. difficile will rapidly increase in numbers.
Birth control/Oral Contraceptives
This is birth control that is taken orally.
Estrogen is used in birth control pills and when women take them it can cause them to have too much estrogen in their bodies. Excess estrogen can cause/lead to the overgrowth of Candida which can lead to leaky gut.
Medications can also irritate the lining of the intestine and damage the mucus layers which can lead to leaky gut.
3. Diet
Bread and butter. Image via pixabay. |
Did you know that the consumption of certain foods can cause a leaky gut? Well, some can! Foods that can cause a leaky gut are:
- Gluten (Gluten is found in wheat, rye, barley, and spelt)
- Soy
- Milk/dairy
- Highly processed foods (These can deplete your good bacteria)
Chronic
inflammation ---- cytokines destroy foreign invaders and also your cells
responds
The
immune system ----------------------->
by causing inflammation
to
substances it
recognizes
as
harmful
Inflammation
is a protection mechanism, however, chronic inflammation is associated with
leaky gut and many diseases.
Gluten
as a foreign invader ------> immune system produce inflammation to destroy
them
And
as more and more enters the bloodstream it creates more inflammation and
eventually, it will attack your tissues. Now, your immune system starts
making antibodies against these substances - it recognizes them as foreign
invaders.
Many
of these foreign invaders look similar to our body cells and the immune system
can get confused and accidentally attack your own tissues - known as molecular
mimicry.
When
the body attacks its own tissues ---------> autoimmune disease
Now
whichever autoimmune disease develops is determined by which tissues are being
attacked. So if it’s the thyroid gland, it could result in Hashimoto's and so
on. When it attacks the lining of the small intestine as mentioned above it can
cause a leaky gut.
An
example with: gluten
Zonulin
(protein) ----------------> regulates the tight junctions of the small
intestine
Gluten
increases the levels of the protein zonulin which opens up the spaces between
the intestinal cells (for people who have a gluten sensitivity) and this causes
leaky gut.
Also,
deemed
Gluten
(For people with gluten intolerance) --------------------> causes inflammation
a foreign |
invader by
|
the immune |
system | can lead
|
|
V
to autoimmune disease
such as Celiac disease or
headaches, joint
pain, leaky gut, etc.
pain, leaky gut, etc.
Pesticides
How are pesticides related to our diet? Well, pesticides are used on foods and we are eating those foods.
Why are pesticides used on foods?
Farmers are using pesticides to kill pests, weeds, and fungus and as a result, they end up in/on our food and water.
So what happens when pesticides end up in our food and water?
Glyphosate is the lead ingredient in RoundUp and it changes the balance of the bacteria in the microbiome (8) and that leads to a leaky gut as already explain about.
Examples of some foods that contain pesticides are spinach, strawberries, tomatoes, potatoes, and apples.
Alcohol
Excessive alcohol consumption can lead to a leaky gut (9).
Alcohol and intestinal bacteria
The overconsumption of alcohol can promote the overgrowth of Gram-negative bacteria in the intestine which will result in increased production of endotoxin.
The overconsumption of alcohol can lead to intestinal mucosal damage which can lead to a leaky gut and can result in endotoxins to pass which can contribute to liver damage.
4. Chronic stress
Stress is never a good thing and leaky gut happens to be one of those reasons why because chronic stress can lead to leaky gut.
How?
Well, stress can disrupt the balance of healthy bacteria in the gut which results in gut lining becomes damaged which can lead to the development of a leaky gut. Additionally, an overgrowth of bacteria can occur.
When the word stress is mentioned we most often think of emotional stress (well I know I have). There are other stresses like pesticides in food, exhaust fumes from vehicles, GMOs, etc. that also put stress on our systems which results in leaky gut.
5. Environmental toxins
6. Infections
7. Burn injury (10)
Some human disease like:
Autoimmune diseases (11)
Some autoimmune diseases that can result due to a leaky gut are:
- Celiac disease
- (12) Inflammatory bowel disease (IBD) - Crohn's Disease (CD)
- Systemic lupus erythematosus
- Type 1 diabetes
- Multiple sclerosis
- Autoimmune hepatitis
Well apart from some foods like gluten and so on as already mentioned above:
As a result of a leaky gut foreign substances (undigested food particles, waste products, bacteria, and toxins) escapes into the bloodstream as mentioned above. The immune system will mistake these foreign substances as a foreign invader and as a result, will create antibodies to destroy them. Also, the immune system will attack the tissues of the body which will cause autoimmune disease. This could be the skin or thyroid, etc.
- fatigue
- gas
- bloating
- diarrhea
- constipation
- skin conditions like rashes, eczema (13)
- headache
- depression
- anxiety
- joint pain
- nutritional deficiencies
- autoimmune diseases
- food allergies and sensitivities
- Eczema
- Anxiety
- Weight gain
How to heal a leaky gut?
You can do so by making changes in your diet like you should avoid the causes of a leaky gut.
A leaky gut can be healed by:
- Certain foods
A study:
Lamprecht et al. (2012) discussed in their paper that there is an increased occurrence of gastrointestinal symptoms in athletes that are exposed to high intense exercise and that the gastrointestinal symptoms have been associated with alterations in intestinal permeability and decreased barrier function. So they observed the effects of probiotic supplementation on markers of the intestinal barrier, oxidation, and inflammation, at rest and after intense exercise of 24 trained men. The authors concluded that "the probiotic treatment decreased Zonulin in feces, a marker indicating enhanced gut permeability" (16).
Beneficial microbes in probiotics are vital to maintain balance and prevent pathogenic infections like C. difficile. Additionally, take probiotics when taking antibiotics.
- Bone broth
- Fiber-rich foods
These foods feed the good bacteria in the gut.
- Control stress
Read: Ways to cope with stress
- Avoid using antibiotics as much as possible.
- Get plenty of sleep
- Avoid pesticides
Organic foods can be expensive but you don't have to purchase all foods organic. Some are actually ok so look for those.
- L - Glutamine, and zinc for the Preservation of intestinal epithelial barrier function.
These should be on your leaky gut grocery list
- Bone broth
You can get the powder or liquid (already made) ones or you can get ingredients to make it like bones and so on and make it yourself from scratch. It takes hours to make from scratch so you can make a huge batch and store it for later use. Also, some people prefer homemade ones better.
I have a post here on bone broth and some of the things I talked about are what it is, there are a few recipes, ways to eat it and so on. If you want to check it out then you can do so here: Bone broth benefits and recipes
- Probiotics
Check my post on what microorganisms your probiotic should contain.
Probiotic supplement
- Prebiotics
Healthy bacteria feed on them.
- Pesticide-free foods (organic foods and filtered water)
To achieve this you should buy organic foods. However, some are safe to buy as non-organic as already mentioned above so that's great for your wallet. Additionally, drink filtered water.
- Non-alcoholic drinks
Find ones that taste good. I'm not saying that you have to completely stop drinking alcoholic drinks because a little alcohol won't lead to a leaky gut but the overconsumption of alcohol will and so when you crave an alcoholic drink you should grab a non alcoholic one instead some of the time.
- Gluten-free products
Avoid products that are made of wheat, rye, barley and spelt because gluten is found in them.
So, therefore, buy gluten-free flour, pasta and so on.
- Soy free
- Dairy free
There are tons of dairy-free milk available these days that you can choose from and some of them are:
almond milk, coconut milk, oat milk, and rice milk just to name a few.
Conclusion
There is no actual proof or Scientific evidence that shows that leaky gut is directly linked to disease or is the cause for the development of disease and so leaky gut is not recognized by most doctors.
However, a damaged epithelial lining is associated with many diseases or a leaky gut is associated with many disease states. Lastly, there are many research studies out there on this topic.
References
Avoid products that are made of wheat, rye, barley and spelt because gluten is found in them.
So, therefore, buy gluten-free flour, pasta and so on.
- Soy free
- Dairy free
There are tons of dairy-free milk available these days that you can choose from and some of them are:
almond milk, coconut milk, oat milk, and rice milk just to name a few.
Conclusion
There is no actual proof or Scientific evidence that shows that leaky gut is directly linked to disease or is the cause for the development of disease and so leaky gut is not recognized by most doctors.
However, a damaged epithelial lining is associated with many diseases or a leaky gut is associated with many disease states. Lastly, there are many research studies out there on this topic.
References
1. Palmer, C., Bik, E. M., DiGiulio, D. B., Relman, D. A., & Brown, P. O. (2007). Development of the human infant intestinal microbiota. PLoS biology, 5(7), e177. doi:10.1371/journal.pbio.0050177
2. Zhang, Y. J., Li, S., Gan, R. Y., Zhou, T., Xu, D. P., & Li, H. B. (2015). Impacts of gut bacteria on human health and diseases. International journal of molecular sciences, 16(4), 7493–7519. doi:10.3390/ijms16047493
3. Bischoff, S. C., Barbara, G., Buurman, W., Ockhuizen, T., Schulzke, J. D., Serino, M., … Wells, J. M. (2014). Intestinal permeability--a new target for disease prevention and therapy. BMC gastroenterology, 14, 189. doi:10.1186/s12876-014-0189-7
4. Wrzosek, L., Miquel, S., Noordine, M. L., Bouet, S., Joncquel Chevalier-Curt, M., Robert, V., … Thomas, M. (2013). Bacteroides thetaiotaomicron and Faecalibacterium prausnitzii influence the production of mucus glycans and the development of goblet cells in the colonic epithelium of a gnotobiotic model rodent. BMC biology, 11, 61. doi:10.1186/1741-7007-11-61
5. Morgan, X. C., Tickle, T. L., Sokol, H., Gevers, D., Devaney, K. L., Ward, D. V., … Huttenhower, C. (2012). Dysfunction of the intestinal microbiome in inflammatory bowel disease and treatment. Genome biology, 13(9), R79. doi:10.1186/gb-2012-13-9-r79
6. Kho, Z. Y., & Lal, S. K. (2018). The Human Gut Microbiome - A Potential Controller of Wellness and Disease. Frontiers in microbiology, 9, 1835. doi:10.3389/fmicb.2018.01835
7. Dethlefsen, L., Huse, S., Sogin, M. L., & Relman, D. A. (2008). The pervasive effects of an antibiotic on the human gut microbiota, as revealed by deep 16S rRNA sequencing. PLoS biology, 6(11), e280. doi:10.1371/journal.pbio.0060280
8. Samsel, A., & Seneff, S. (2013). Glyphosate, pathways to modern diseases II: Celiac sprue and gluten intolerance. Interdisciplinary toxicology, 6(4), 159–184. doi:10.2478/intox-2013-0026
9. Bishehsari, F., Magno, E., Swanson, G., Desai, V., Voigt, R. M., Forsyth, C. B., & Keshavarzian, A. (2017). Alcohol and Gut-Derived Inflammation. Alcohol research : current reviews, 38(2), 163–171.
10. Earley, Z. M., Akhtar, S., Green, S. J., Naqib, A., Khan, O., Cannon, A. R., … Choudhry, M. A. (2015). Burn Injury Alters the Intestinal Microbiome and Increases Gut Permeability and Bacterial Translocation. PloS one, 10(7), e0129996. doi:10.1371/journal.pone.0129996
11. Mu, Q., Kirby, J., Reilly, C. M., & Luo, X. M. (2017). Leaky Gut As a Danger Signal for Autoimmune Diseases. Frontiers in immunology, 8, 598. doi:10.3389/fimmu.2017.00598
12. Michielan, A., & D'IncĂ , R. (2015). Intestinal Permeability in Inflammatory Bowel Disease: Pathogenesis, Clinical Evaluation, and Therapy of Leaky Gut. Mediators of inflammation, 2015, 628157. doi:10.1155/2015/628157
13. Forno, E., Onderdonk, A. B., McCracken, J., Litonjua, A. A., Laskey, D., Delaney, M. L., … CeledĂłn, J. C. (2008). Diversity of the gut microbiota and eczema in early life. Clinical and molecular allergy : CMA, 6, 11. doi:10.1186/1476-7961-6-11
14. Ahrne, S., & Hagslatt, M. L. (2011). Effect of lactobacilli on paracellular permeability in the gut. Nutrients, 3(1), 104–117. doi:10.3390/nu3010104
15. Zakostelska, Z., Kverka, M., Klimesova, K., Rossmann, P., Mrazek, J., Kopecny, J., … Tlaskalova-Hogenova, H. (2011). Lysate of probiotic Lactobacillus casei DN-114 001 ameliorates colitis by strengthening the gut barrier function and changing the gut microenvironment. PloS one, 6(11), e27961. doi:10.1371/journal.pone.0027961
16. Lamprecht, M., Bogner, S., Schippinger, G., Steinbauer, K., Fankhauser, F., Hallstroem, S., … Greilberger, J. F. (2012). Probiotic supplementation affects markers of intestinal barrier, oxidation, and inflammation in trained men; a randomized, double-blinded, placebo-controlled trial. Journal of the International Society of Sports Nutrition, 9(1), 45. doi:10.1186/1550-2783-9-45
5. Morgan, X. C., Tickle, T. L., Sokol, H., Gevers, D., Devaney, K. L., Ward, D. V., … Huttenhower, C. (2012). Dysfunction of the intestinal microbiome in inflammatory bowel disease and treatment. Genome biology, 13(9), R79. doi:10.1186/gb-2012-13-9-r79
6. Kho, Z. Y., & Lal, S. K. (2018). The Human Gut Microbiome - A Potential Controller of Wellness and Disease. Frontiers in microbiology, 9, 1835. doi:10.3389/fmicb.2018.01835
7. Dethlefsen, L., Huse, S., Sogin, M. L., & Relman, D. A. (2008). The pervasive effects of an antibiotic on the human gut microbiota, as revealed by deep 16S rRNA sequencing. PLoS biology, 6(11), e280. doi:10.1371/journal.pbio.0060280
8. Samsel, A., & Seneff, S. (2013). Glyphosate, pathways to modern diseases II: Celiac sprue and gluten intolerance. Interdisciplinary toxicology, 6(4), 159–184. doi:10.2478/intox-2013-0026
9. Bishehsari, F., Magno, E., Swanson, G., Desai, V., Voigt, R. M., Forsyth, C. B., & Keshavarzian, A. (2017). Alcohol and Gut-Derived Inflammation. Alcohol research : current reviews, 38(2), 163–171.
10. Earley, Z. M., Akhtar, S., Green, S. J., Naqib, A., Khan, O., Cannon, A. R., … Choudhry, M. A. (2015). Burn Injury Alters the Intestinal Microbiome and Increases Gut Permeability and Bacterial Translocation. PloS one, 10(7), e0129996. doi:10.1371/journal.pone.0129996
11. Mu, Q., Kirby, J., Reilly, C. M., & Luo, X. M. (2017). Leaky Gut As a Danger Signal for Autoimmune Diseases. Frontiers in immunology, 8, 598. doi:10.3389/fimmu.2017.00598
12. Michielan, A., & D'IncĂ , R. (2015). Intestinal Permeability in Inflammatory Bowel Disease: Pathogenesis, Clinical Evaluation, and Therapy of Leaky Gut. Mediators of inflammation, 2015, 628157. doi:10.1155/2015/628157
13. Forno, E., Onderdonk, A. B., McCracken, J., Litonjua, A. A., Laskey, D., Delaney, M. L., … CeledĂłn, J. C. (2008). Diversity of the gut microbiota and eczema in early life. Clinical and molecular allergy : CMA, 6, 11. doi:10.1186/1476-7961-6-11
14. Ahrne, S., & Hagslatt, M. L. (2011). Effect of lactobacilli on paracellular permeability in the gut. Nutrients, 3(1), 104–117. doi:10.3390/nu3010104
15. Zakostelska, Z., Kverka, M., Klimesova, K., Rossmann, P., Mrazek, J., Kopecny, J., … Tlaskalova-Hogenova, H. (2011). Lysate of probiotic Lactobacillus casei DN-114 001 ameliorates colitis by strengthening the gut barrier function and changing the gut microenvironment. PloS one, 6(11), e27961. doi:10.1371/journal.pone.0027961
16. Lamprecht, M., Bogner, S., Schippinger, G., Steinbauer, K., Fankhauser, F., Hallstroem, S., … Greilberger, J. F. (2012). Probiotic supplementation affects markers of intestinal barrier, oxidation, and inflammation in trained men; a randomized, double-blinded, placebo-controlled trial. Journal of the International Society of Sports Nutrition, 9(1), 45. doi:10.1186/1550-2783-9-45