The Top 5 Root Causes of IBS That You Need to Know About

Last week we talked about why you should never settle for an IBS diagnosis and how IBS is not a single disease with a single cause. We now know that it’s a whole host of diagnosable health issues, which is why we must look further for complete healing. And while the exact root cause, or combination of causes, is unique to each person, this week I want to share with you the five that I most commonly see in my ‘IBS’ clients. Because of the recent advances in gut health research and testing, many of these causes might not be on the radar of your local doctor... not yet, anyway. It’s really motivating stuff, because it means there is likely a very treatable reason for your IBS symptoms, and what could be more reassuring than knowing it’s not “all in your head”?

Here is a summary of what we are going to cover:
>  What exactly is a ‘root cause’ and why is it so important?
>  The top 5 root causes of IBS that your doctor probably isn’t testing for
>  Why you likely have more than one root causes contributing to your IBS symptom


What exactly is a ‘root cause’ and why is it important?

Healing the gut is like any complex problem solving activity; you need to look beyond the symptoms and focus instead on the underlying root cause/s. Suppressing symptoms may result in short-term health improvement, but your original symptoms are likely to come back, and often progressively worsen, unless the underlying root cause is identified and treated.

Here’s just one example of how continuing to ask “why?” can start to get you closer to the real cause of your symptoms, and closer to a solution that actually works:

Symptom: I have bloating
Why? #1: Because I eat certain foods like high-FODMAPs
Why? #2: Because the bacteria in my GI tract are fermenting the carbohydrate from the food in my small intestine, instead of my large intestine
Why? #3: Because I have small intestinal bacterial overgrowth (SIBO)
Why? #4: Because my migrating motor complex (MMC) is not functioning correctly
Why? #5: Because I had food poisoning overseas last year, and after my immune system attacked and killed that bacteria, it is now attacking my MMC, causing my SIBO to constantly relapse.

I really hope that this example illustrates the point that if you stop at the first ‘Why?’, you might be eating a restricted low-FODMAP diet forever, constantly trying to manage symptoms as your health deteriorates. Only once you start to ask better questions (or more Why’s), can you get the answers you need to finally understand and heal your IBS symptoms.

So let’s get into the root causes. It’s not an exhaustive list by any means, but these are definitely the most common root causes of IBS-symptoms I see in my practice.

Root cause #1 - Small Intestinal Bacterial Overgrowth (SIBO)

I’ve written a three part series on SIBO, but here’s the abbreviated version. SIBO is characterised by an increased number and/or abnormal type of bacteria in the small intestine (1). Because these bacteria generally live in the large intestine, they are mostly species that ferment carbohydrates into hydrogen gas (H2) or archaea (not technically bacteria) that produce methane gas (CH4).

While both hydrogen and methane types typically result in abdominal bloating and distention, as with IBS sufferers, SIBO types are divided into one of three different categories;  diarrhoea-dominant, constipation-dominant or alternating variations of both… sound familiar? Well that’s because, according to some studies, as many as 85% of those diagnosed with IBS actually have SIBO (2).

The diarrhoea-dominant SIBO is generally the result of carbohydrate-fermenting bacteria that produce hydrogen gas in the small intestine. The constipation sufferers, on the other hand, generally have archaea, not technically bacteria, to blame. During the fermentation of carbohydrates, archaea, such as M.smithii, feed off the hydrogen produced by bacteria and produce a by-product of their own; methane (3). As with hydrogen, methane gas in the small intestine will cause abdominal bloating, plus a much bigger problem - slowed transit time and ultimately, constipation (4).

Just in case you weren’t clear on the link, here are the most common symptoms of the various SIBO types, many of which overlap with those of IBS:
>  Bloating within one hour after meals
>  Chronic diarrhoea or constipation or alternating constipation and diarrhoea
>  Burping or reflux after meals
>  Foul smelling gas
>  Stomach gurgling and discomfort or cramping

Root cause #2 - Dysbiosis of the Gut Microbiome

Our gut houses a complex community of over 100 trillion microorganisms that influence our human physiology, metabolism, nutrition and immune function, collectively referred to as our microbiome (5).

The recent explosion of research on the ecosystem residing in our intestines, called our gut-microbiome, has provided support for the concept that a disruption of the gut-biome may cause the onset and exacerbation of IBS-type symptoms (6). Recent studies have shown that up to 83% of patients with IBS have abnormal faecal biomarkers, and 73 percent have intestinal dysbiosis (i.e. a disrupted gut microbiome) (7).

Often the result of antibiotics, a dysbiosis has traditionally been difficult to detect, using standard testing. After all, there is often nothing to actually find. It is, instead, a lack of number or diversity of beneficial bacteria that leads to the gradual onset of IBS-type symptoms, rather than the presence of any particularly bad bug. The bad/worse news is that even a single course of antibiotics can permanently alter the gut flora and increase your risk of getting dangerous bacteria, such as Clostridium difficile (8), which causes horrendous diarrhea and IBS symptoms.

Root cause #3 - Intestinal Hyperpermeability (Leaky Gut)

Acting as the body’s second skin, the Epithelial Cells of the small intestine (i.e., the intestinal lining) are like the fence separating the inside of your intestines and your bloodstream. Their role is to control what is allowed access into your bloodstream, such as nutrients, and what is not allowed in, like pathogens, toxins and undigested food particles (called macromolecules).

When you have a ‘leaky gut’, it’s like the doors are open between your intestines from your bloodstream. Macromolecules of food, toxins and pathogens that normally aren’t allowed through, now flow freely into your bloodstream, making your immune system wake up and start fighting. This is called an inflammatory immune response and causes all sorts of GI symptoms.

Defects in intestinal barrier function are associated with diseases of the GI tract. There is growing evidence that increases in intestinal permeability plays a pathogenic role in inflammatory bowel disease and functional bowel disorders, such as irritable bowel syndrome (9).

Root cause #4 - Gut infections

When we talk about gut infections, I’m referring to infections anywhere from the stomach right through to the small intestine and the colon. They are caused by pathogens, the most common being:
> Parasites: Blastocystis hominis, Entamoeba histolytica, Giardia lamblia, Cryptosporidium parvum, Dientamoeba fragilis
> Bacteria: Helicobacter pylori, Citrobacter, Campylobacter, Clostridium difficile, Klebsiella pneumoniae
> Fungi/Yeast: Candida albicans

While this isn’t an exhaustive list, parasites, bacteria and fungi/yeast are by far the most common gut infections I see in my practice and the ones I specialise in treating.

Overseas travel, food poisoning, overly affectionate pets or an outbreak in your town’s water supply can all give you a nasty bug. Unfortunately, pathogens are just a normal part of life in every country on Earth, it’s whether your immune system is strong enough to fight them off that really matters. It’s why we have stomach acid, good bacteria in our gut and an immune system to fight back and keep these ‘bad guys’ at bay (10, 11). But, if you are stressed, intoxicated, fatigued, have food sensitivities or any other illness or health condition, your immune system is likely to be compromised, increasing your risk of a gut infection with potentially lasting effects, like IBS symptoms (12, 13, 14).

Prior use of antibiotics (often used to kill another gut infection) is also a very common cause of gut infections, particularly Candida or overgrowths like SIBO (15). While antibiotics can sometimes be effective at killing the primary bacterial infection, by destroying all the good bacteria at the same time, they also create an environment for opportunistic pathogens and overgrowths to proliferate and cause long-term chronic conditions (16).

Here are a couple of ways you can figure out if a gut infection is contributing to your IBS symptoms:

>  Cyclical diarrhoea - most parasites have specific life cycles and result in cyclical symptoms, such as diarrhoea. So, if you are doing ok for a week or two and then have an intense flare-up of symptoms for a few days and then do ok for another week or two and so on, that can be a real sign of a parasite.

>  Constipation - pathogenic bacteria can give off neurotoxins to ‘paralyse’ the muscles around the intestines, slowing peristalsis (intestinal movement) so that the organisms don’t get removed with the stool as easily as they may have before. Constipation can then create an environment in which pathogens can further grow and proliferate (17, 18).

>  Gas and bloating - gas results when bacteria ferment intestinal contents, commonly fermentable dietary fibre and carbohydrates. SIBO (discussed above) is a common example of this and why many people see reduced symptoms on a low-FODMAP diet which is low in fermentable foods (19).

>  Reflux, heartburn or indigestion - some pathogens, like H.pylori, affect stomach acid production and our ability to digest foods properly, and can result in reflux, heartburn and indigestion-type symptoms (20, 21).

>  Real food diet failures - if you still have IBS symptoms after you’ve tried any of the real food / low allergen diets like SCD, GAPS, Paleo or low-FODMAP diets for more than six weeks, then there is a high chance you have a gut infection.

>  Secondary symptoms - like fatigue, hormone imbalances, weight gain, insomnia, anxiety and malabsorption from a Leaky Gut can all be the result of a gut infection (22, 23).

Root cause #5 - Food sensitivities

Clients with food sensitivities commonly present with many of the common IBS symptoms of gas, bloating, constipation, diarrhoea and abdominal pain. The most prevalent food triggers for IBS sufferers I see include reactions to gluten, dairy, eggs and nuts, amongst others. These include true allergies (IgE-mediated immune responses) or more mild intolerances (IgG-mediated immune response) as well as enzyme deficiencies leading to conditions like lactose or fructose malabsorption.

Recent research has suggested that food allergy and intolerance should be considered a possible cause of IBS (24). In my own clinical experience, I’ve definitely found food intolerances and malabsorption to be a very common contributing factor to IBS-symptoms. It is also worth noting that food intolerances are themselves, often caused by some of the conditions discussed above, particularly a leaky gut (I’ve written a whole blog post on the connection between leaky gut and food sensitivities here).

So while food triggers can definitely make symptoms worse, generally they aren’t the end of the line, but rather a sign of a deeper root cause. And when that underlying root cause is identified and healed, avoiding foods forever should not be needed.

Or it could be a combination of the above?

So many times I see clients who have SIBO, a gut infection of some variety, dysbiosis and a leaky gut. If we test for food sensitivities, they usually have a few of these mixed in to further complicate healing. This was my exact combination.

I had methane dominant SIBO, dysbiosis with limited bifidobacterium and next to no lactobacillus species in my gut (the leakiest gut I have come across so far via testing), Blastocystis hominis (parasite), Citrobacter, Klebsiella, and a whole list of other bad bacteria, Candida yeast and food sensitivities to the proteins in dairy, eggs, gluten-containing grains and a few other random foods. In my gut’s defense, I lived on antibiotics and a processed foods diet until my early-twenties... With a list like this, it is hugely important to know everything you are dealing with so you can make a plan to address them all in sequence when healing. And it is also important to understand that fixing each one on it’s own, without addressing the other root causes, will not remove all your symptoms.

So what next?

I’m sure your next question is: “Bel, how do we work out whether we have these 5 things?” The answer is: Testing! We are going to cover this off next week so I can give you lots of detail.

I really hope the content from this post helps you understand why you need to keep searching for the root cause of your IBS. Your doctor has hopefully ruled out all the nasty and life-threatening stuff, so let’s get to the functional root cause that is completely healable. Your health is worth it.

Healing the gut is a journey. If you are ready to begin yours, please head to the Work With Us page to learn more about how we work online with clients in many countries to test for and treat the various root causes of IBS symptoms and other GI conditions.


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