Why I Don’t Recommend Commercial Stool Tests (Aka Microbiome Testing) Just Yet
Controversial topic here: let’s talk about commercial stool analysis testing (aka gut-microbiome testing)!
You may have seen these tests recommended online by various influencers, or perhaps your natural practitioner is encouraging you to have one done. But you recognize it’s expensive, and so you’re wondering - is it worth it?
The most common commercial ones are the GI MAP or Viome Tests - yes, the ones with amazing marketing on their website. As I’ve mentioned in other blogs, don’t be fooled by good marketing when trying to make decisions about your gut health.
Keep reading to learn more about why I don’t recommend home stool testing (for now).
What Is Home Stool Testing?
Home stool tests claim to test for GI pathogens, opportunistic organisms, normal flora, and markers of GI health including bacteria, viruses, fungi, and parasites.
Why stool? Well, it spends a very long time in our gut, of course! Stool is used because it is made up of many things such as water, insoluble (or indigestible) fiber, but most importantly, various types of bacteria that reside in our gut.
Many people are interested in this test for identifying gut-related issues and dietary problems to help solve their complaints.
Generally speaking, there are two types of stool tests:
Clinical Stool Testing: One is used in clinical settings, where stool samples are taken so that the bacteria found can be grown in a lab to determine the cause of adverse symptoms such as diarrhea. These would be recommended by a medical professional, likely either your general physician or gastroenterologist.
The stool will be checked by a lab technician for color, consistency, amount, shape, and presence of any mucus [1]. The stool may be examined for hidden (aka occult) blood, fat, meat fibers, bile, or white blood cells. The pH of the stool also may be measured. A stool culture may be done to see if certain bacteria are causing an infection [1].
To be clear, these clinical tests recommended by physicians are NOT the tests I will be discussing in this article.
Commercial Stool Testing: The second type of stool testing that we will be discussing in this article is known as commercial stool testing. This method extracts DNA from the stool to identify the type and number of bacteria present.
These tests can be easily purchased online, and you do not need a medical professional to provide a requisition for you to get one done.
As mentioned above, some examples of these ‘commercial stool tests’ include the GI Microbial Assay Plus (GI-MAP) or the Viome Gut Intelligence™ Test.
What Is the Gut Microbiome?
To get on the same page while discussing these tests that assess your ‘gut health’, let’s be clear on what gut health actually is! Our gut, also called our gastrointestinal (GI) tract, is the entire pathway from our mouth, through our esophagus, stomach, small intestine, large intestine and anus.
Our gut houses our ‘gut-microbiome’ which includes a variety of microorganisms including bacteria, archaea, fungi, and viruses. These amazing microbes are responsible for many of the functions in our body such as metabolism, digestion, immunity, production of certain nutrients, mental health, and are influenced by things like genetics, disease, dietary habits, stress, and more.
Experts agree, a ‘healthy’ gut microbiome is typically one that has greater diversity of microbiomes in the gut.
On the flip side, low variation of gut microbes can lead to poor immunity, impaired gut barrier functions, and high levels of lipopolysaccharides (LPS) in the plasma. LPS is a part of the gram-negative bacteria that cause chain reactions that result in inflammation of the adipose (fat) tissues, and increase the risk of developing obesity and metabolic syndrome.
You may want to read Gut Microbiome: What Is It and How Can We Better Support Our Gut Bugs?
What Can (or can’t) Commercial Home Stool Analysis Testing Show Us?
For now, evidence is limited and lacking on the significance of the results we receive from these home tests.
Here are the main problems with these commercial tests:
Truth be told, as of 2023, scientists have not yet been able to accurately ‘quantify’ a healthy gut microbiome [2,3].
We know that an “unhealthy microbiome” likely has: Low microbial richness or diversity; low levels of short chain fatty acid-producing bacteria.
Experts agree that a healthy gut microbiome should have a diversity of microbes and species, but what those numbers look like, is not yet defined or agreed upon.
These companies actually came up (aka. made-up) with their own parameters for what they consider high, normal, or low levels of different microbes. This is a problem because companies should not be creating their own cut off parameters; we want to rely on external studies that are not biased towards a company's profits and internal motives.
It goes without saying, most of us want to know WHY we are having symptoms and for many who have been dealing with these problems for years, we become ready to try almost anything. Unfortunately, these companies may take advantage of that fact.
So in the end, a lot of these companies will sell you a test that is likely to tell you that you have a problem, and then sell you the solution, getting you to spend more money.
The stool we provide for these tests (which you literally poop out into the sample bag) does not accurately reflect the microbiome at your intestinal mucosal level. In fact, the stool microbiome is actually different from the luminal (aka intestinal tract) microbiome, which essentially varies depending on each part of the gastrointestinal tract!
These test results categorize organisms as good vs. pathogenic - this is only one part of the picture, it’s important to remember that your gut microbiome will always contain some pathogenic bacteria, it's the balance that matters.
Further, it's the community as a whole and how the species interact that actually impact inflammation and disease in the gut.
Taking one stool sample can’t give you a full picture of the health of your gut microbiome. As mentioned above, the gut microbiome is influenced by many changing environmental factors such as diet and stress. With these constant changes, it makes it near impossible to diagnose medical issues, candida or fungal overgrowth [4].
They are incredibly expensive - and when you are already spending money on doctor’s visits, fancy supplements, it can all really add up and lead to even more stress.
So in short, there are many holes in terms of the actual evidence, clinical use and relevance of these home stool tests.
Maybe one day microbiome tests will be more accurate and provide insight, but for now, it’s a pass.
What Should You Do Instead?
While getting your stool analyzed and seeing what types and amounts of bacteria are present, I recommend saving your money.
What do I recommend instead?
Get the appropriate medical tests done to uncover underlying gut issues: Seek care from a medical professional who can recommend the appropriate testing. For example (not an exhaustive list):
Stool Sample Testing: through the recommendation of an Medical Doctor (MD) is a more reliable test for parasites or other pathogens.
Blood testing: For nutrient deficiencies, compromised liver health, celiac disease or H Pylori.
Hydrogen Methane Breath Testing: This is the best testing option we currently have to diagnose Small Intestinal Bacterial Overgrowth (SIBO).
Colonoscopy: To assess any signs of disease and/or inflammation in your large intestine.
There are many more - seek support from a Medical Doctor to help you to receive the proper investigations.
Support your microbiome through evidence-based diet and lifestyle changes: this includes stress, sleep, a gut-friendly diet, and limiting substances that harm good bacteria (such as alcohol and illicit drugs).
Work with a specialized Dietitian: We can help you to take a deeper look into your diet, lifestyle and medical history to develop a tailored plan to improve your gut symptoms and rebalance your microbiome.
P.S. Wondering exactly how to support a gut friendly diet and robust gut-microbiome with proven meal planning and prepping strategies?
Grab the Ultimate Guide to Gut-Friendly Diet Meal Prep & Planning Now!
Additional Reading
You may want to also read these articles:
The Takeaway
So, where does this leave us? In the face of uncertainty and questionable efficacy, it's prudent to consider alternative avenues for assessing and supporting our gut health. Seeking guidance from medical professionals and undergoing specific diagnostic tests can provide more reliable insights.
Additionally, making evidence-based dietary and lifestyle changes, supported by a specialized dietitian and healthcare providers, remains a solid approach to nurturing your amazing gut microbiome. If you’re interested in working with a specialized gut health Dietitian, apply for my 1-1 coaching program.
While the idea of home stool testing holds promise, the current landscape is riddled with uncertainties and potential pitfalls. As we navigate the ever-evolving field of gut health, let's proceed with caution, prioritize sound medical advice, and focus on evidence-based strategies to cultivate a healthy microbiome. The journey towards understanding our gut remains an exciting one, but for now, the verdict on home stool testing leans towards a cautious pass!
Summary:
Home commercial stool testing, with enticing promises of revealing answers about your gut health, is trending, but the science behind it is still evolving, leaving many questions unanswered.
These tests suffer from a lack of standardized parameters, with companies setting their own criteria, raising concerns about objectivity and profit-driven motives.
Home stool tests offer only a limited snapshot of the complex gut microbiome, unable to capture its dynamic nature influenced by various factors like diet and stress.
Instead of relying solely on these tests, it's advisable to consult medical professionals, undergo recommended diagnostic tests, and focus on evidence-based dietary and lifestyle changes to support gut health.
Any questions about commercial stool tests? Comment below and let me know your thoughts on this controversial topic!
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References:
[1] Stool analysis. MyHealth.Alberta.ca Government of Alberta Personal Health Portal. (n.d.). https://myhealth.alberta.ca/Health/Pages/conditions.aspx?hwid=aa80714
[2] Muller, E., Algavi, Y. M., & Borenstein, E. (2021). A meta-analysis study of the robustness and universality of gut microbiome-metabolome associations. Microbiome, 9(1), 203. https://doi.org/10.1186/s40168-021-01149-z
[3] Staley, C., Kaiser, T., & Khoruts, A. (2018). Clinician Guide to Microbiome Testing. Digestive Diseases and Sciences, 63(12), 3167–3177. https://doi.org/10.1007/s10620-018-5299-6
[4] Allaband, C., McDonald, D., Vázquez-Baeza, Y., Minich, J. J., Tripathi, A., Brenner, D. A., Loomba, R., Smarr, L., Sandborn, W. J., Schnabl, B., Dorrestein, P., Zarrinpar, A., & Knight, R. (2019). Microbiome 101: Studying, Analyzing, and Interpreting Gut Microbiome Data for Clinicians. Clinical Gastroenterology and Hepatology : The Official Clinical Practice Journal of the American Gastroenterological Association, 17(2), 218–230. https://doi.org/10.1016/j.cgh.2018.09.017