Irritable bowel syndrome (IBS), like many chronic conditions, requires a clinical diagnosis. There’s no test to determine whether or not you have IBS. This means that IBS is diagnosed based solely on symptoms, and that if you have chronic symptoms that are consistent with IBS—diarrhea, constipation, abdominal pain, and bloating—then you have IBS, and if you don’t have these symptoms, then you don’t have IBS.
Conditions that require clinical diagnosis aren’t any less significant than conditions that require test results for diagnosis. Both approaches to diagnosis are important and necessary, given that not all symptoms can be measured, and not everything that can be measured manifests as symptoms.
There’s a common misperception, however, that because tests aren’t required for clinical diagnosis, then tests aren’t required at all for these conditions. That because IBS can be diagnosed without tests, then there’s no need for tests.
I couldn’t disagree more.
If your practitioner’s objective is to suppress your symptoms with medication, without consideration of the causes, then, sure, it doesn’t make sense to do any tests. But if your practitioner’s objective is to help you to resolve your symptoms, by addressing the causes with diet, supplements, and lifestyle, then conducting tests to identify the causes is paramount.
Regardless of who your practitioner is, I imagine you resonate more with the latter approach than the former—that you’re more interested in the prospect of resolving your symptoms than suppressing them—so let’s explore five common causes of IBS that most practitioners don’t test for, to best position you to get the data you need to move forward on your journey to better health.
Gluten
Gluten, a protein in wheat, barley, and rye, is perhaps the most commonly overlooked cause of IBS, because most practitioners believe that only people with celiac disease need to avoid gluten, due to the autoimmune reaction to gluten that they experience, in which their immune system inappropriately targets and causes damage to the intestinal barrier.
But it turns out that gluten actually causes intestinal damage in everyone, and not just those with celiac disease, by causing the activation of zonulin (a protein responsible for regulating intestinal barrier function), which then leads to increased intestinal permeability, or leaky gut.1 While leaky gut doesn’t necessarily cause digestive symptoms, it does increase the likelihood of developing immune dysregulation, food sensitivities, and inflammation, all of which increase the likelihood of developing IBS.
What’s more, gluten causes an immune reaction, independent of the effects of zonulin activation, in a significant percentage of those who don’t have celiac disease. This immune reaction, termed non-celiac gluten sensitivity, is a common cause of digestive symptoms that are diagnosed as IBS, such as diarrhea and constipation, that only resolve after strict adherence to a gluten-free diet.2
Dairy
Another common cause of IBS is dairy, and it’s up there with gluten in terms of the number of practitioners who believe that only people with dairy allergy need to avoid dairy. Lactose intolerance, or the inability to properly digest milk sugar, is surprisingly prevalent, affecting 75% of the global population.3
Like gluten, lactose causes an immune reaction, in people with lactose intolerance, that results in inflammation throughout the gastrointestinal tract and ultimately digestive symptoms that are often diagnosed as IBS. Unlike gluten, however, which tends to affect people of all ages, lactose is more effectively broken down and digested in childhood than in adulthood, due to an enzyme, lactase, that decreases in production as we get older.4 The likelihood of developing lactose intolerance thus increases with age, as the ability to digest lactose without provoking an immune reaction decreases.
Parasites
Unfortunately, it’s not just diet that you have to think about when it comes to IBS. Parasites, such as Blastocystis hominis, Giardia lamblia, and Dientamoeba fragilis, are another common cause of IBS that most practitioners don’t test for. I don’t think anyone disputes that certain parasites cause acute digestive symptoms, but I think that the frequency with which parasites cause chronic digestive symptoms is significantly underestimated, and particularly in industrialized countries such as the United States.
The general consensus is that parasites aren’t an issue in the United States, given our modern infrastructure, but this couldn’t be further from the truth. Parasites are a rampant issue in the United States, just as parasites are an issue everywhere else. You can certainly try to minimize your exposure to parasites, by practicing good hygiene and not letting your dog lick your face and not eating anyone else’s food and not drinking anyone else’s drink, but the reality is that you’re constantly exposed to parasites.
The good news is that most parasites don’t cause symptoms, so you don’t have to worry about most parasites. The bad news is that some parasites do, and those are the parasites that you have to worry about and that you should test for, especially if you have IBS.
Bacteria
Bacteria are another cause of IBS that most practitioners don’t test for, despite the obvious importance of bacteria to digestive health. Your gut microbiome is made up of trillions of microorganisms, and 99% of which are bacteria.5 These bacteria are categorized as commensal, opportunistic, and pathogenic, and the levels of bacteria for each category influence whether or not you experience digestive symptoms.
Commensal bacteria, such as Bifidobacterium bifidum, Lactobacillus reuteri, and Akkermansia muciniphila, are considered normal bacteria of the human gut microbiome. Opportunistic bacteria, such as Enterococcus faecalis, Staphylococcus aureus, and Pseudomonas aeruginosa, are also considered normal, harmless bacteria of the gut microbiome, but only at low levels. Pathogenic bacteria, such as Clostridium difficile, Escherichia coli, and Yersinia enterocolitica, are harmful bacteria that are typically acquired through consumption of contaminated food or water.
Digestive symptoms often develop if you have low levels of commensal bacteria, or high levels of opportunistic bacteria, or if you contract pathogenic bacteria at any level. Or, worse, if you have abnormal levels of all three. Maintaining appropriate levels of commensal bacteria and opportunistic bacteria, and eradicating pathogenic bacteria, if present, is thus an important focus for anyone with IBS.
Fungi
Fungi, such as Candida albicans, Saccharomyces cerevisiae, and Rhodotorula mucilaginosa, are yet another cause of IBS. Whereas most bacteria in the human gut microbiome are commensal, most fungi in the gut microbiome are opportunistic, which creates an environment in which even a slight decrease in microbiome diversity causes fungi to overgrow, which causes a further decrease in microbiome diversity, and so on. Such a vicious cycle requires not just a focus on eradicating the fungi, but also, and often more importantly, on restoring microbiome diversity.
The overuse of antibiotics is perhaps the most widely recognized assault on microbiome diversity that sets the stage for fungal overgrowth, but overconsumption of processed foods and refined sugars is an equally important factor to address.
How to identify the causes of your IBS
If you have IBS, and your practitioner hasn’t tested for gluten sensitivity, dairy sensitivity, parasites, bacteria, and fungi, you might be tempted to go to them to ask to be tested for these common causes of IBS. You might expect that they’ll be thrilled that you’re taking initiative, and that of course they’d be happy to order these tests for you, because obviously they’re just as interested as you are in identifying the causes of your IBS so that you can address the causes and recover your health.
And I don’t want to dissuade you from asking your practitioner to order these tests, because you might be in the minority of people who are working with practitioners who are receptive to learning new things, but I do want to warn you that most practitioners are neither trained nor interested in investigating the causes of symptoms.
They’re trained, instead, to diagnose symptoms, and then to treat symptoms with medication, without investigating the causes. They’re trained to manage, rather than reverse, chronic illness.
It’s not that they don’t want to help you. They didn’t become a practitioner to not help people. But their way of helping—by prescribing medication to suppress symptoms—probably isn’t in alignment with how you want to be helped, or how most people with chronic symptoms want to be helped.
So you might not have any luck asking your conventional practitioner to test for gluten sensitivity, dairy sensitivity, parasites, bacteria, and fungi, but that doesn’t mean these tests are difficult to get. It just means you’re not asking the right practitioner.
How we can help
Most Quantify members joined because they were interested in investigating the causes of their chronic symptoms with advanced biomarker tests, but they were working with practitioners who didn’t share that interest. We not only share that interest, but that’s actually our mission: to make at-home biomarker tests and data-driven health coaching available to everyone. We order the tests that your practitioner isn’t interested in ordering—whatever tests you want, at whatever frequency—and we translate the results into actionable steps that you can take to improve your health.
Some of our members, for example, had IBS when they joined, and after identifying the causes of their IBS, and addressing the causes with diet, supplements, and lifestyle strategies, these members were able to reverse their IBS, and get their lives back, despite their practitioners insisting that there was nothing they could do.
If you’re interested in investigating the causes of your IBS, but haven’t gotten anywhere with conventional practitioners, you can schedule a call to learn more about Quantify membership and how we can help you to get the data you need to resolve your symptoms and optimize your health.