IBS, SIBO, and parasites are nearly never the main cause of chronic gut issues. They are almost always secondary — downstream consequences of deeper imbalances — and will frequently reverse on their own once corrective care addresses the real roots: nervous system regulation, a healthy whole-foods diet, histamine control, stress reduction, resolving MCAS, moving out of mold, and identifying sensitivities to dairy and gluten, to name a few.
Parasites are real, and we have plenty of them in the United States — you do not need to travel to a third-world country to encounter them. However, they are most likely not your driving cause for gut issues, especially if your symptoms did not come on at a specific time with a direct correlation — a clear event after which your digestion and health were never the same.
SIBO is always due to a host of other things: dysbiosis, poor diet, blood sugar dysregulation, Epstein-Barr virus, H. pylori, low stomach acid, motility issues, and a long list of other drivers. The same is true of IBS — SIBO and parasites are just a few of the many things lumped under the IBS label, which is really just a label for any chronic gut issues with no known cause. It is completely unhelpful, and actually negatively impactful on health, because once you have the label, doctors often stop there, telling you they have solved the problem.
You can end up with a functional doctor who aggressively focuses on SIBO or parasites, making a sensitive person much worse, or a traditional Western doctor who ignores it all and says there is nothing wrong because your labs are normal. There are always, always real issues causing these symptoms. But they are just symptoms, and we must look at them as such in order to dig deeper. Just starting a protocol to kill off SIBO, taking antacids, or doing an extreme carnivore diet does not address the issues.
Dr. Peter Kan, a board-certified functional neurologist and functional medicine practitioner, speaks to the gut as the second brain. He has shared that when the autonomic nervous system is dysregulated, the gut-brain axis breaks down — motility stalls, digestion weakens, and the environment becomes a perfect breeding ground for overgrowth. You cannot fix the gut without fixing the nervous system that governs it. Autoimmune dysfunction and nervous system dysfunction can impact the gut so immensely that no amount of antimicrobials or restrictive diets will hold until those upstream systems are addressed.
Our environment is making it more and more difficult for the gut microbiome to thrive. Toxins in the air, EMFs, pollutants in the water, poor-quality nutrition in our food, and the excessive access to fast food alongside a lack of whole, nutrient-dense foods all take their toll. Vitamin deficiencies play a huge role in the gut microbiome and digestion, as does histamine intolerance, which is very prevalent in the more sensitive, chronically ill populations.
Dr. Michael Ruscio, a clinical researcher and functional medicine practitioner who looks at gut health from the full perspective of chronic illness, has noted that gut symptoms are a signal, not a sentence. He has shared that the goal is not to endlessly chase and eradicate every organism — it is to build a resilient, well-regulated body where the microbiome can rebalance itself.
Although parasites are very real and there is absolutely a place for detoxing and doing parasite cleanses, particularly in some corners of the functional medicine world, these have been taken too far. Some practitioners are recommending very intense, harsh parasite cleanses that simply cannot be tolerated by those in chronically ill, sensitive states, and are never the starting place. A system must be regulated, calmed, and supported from a micro and macronutrient standpoint to where it feels safe before attempting these. Ironically, when the body is supported and feels safe, its own cleaning and purging systems are "initiated." It can sometimes rid parasites and reverse SIBO/IBS on it's own.
The main takeaway is to understand that these conditions are not actually that — they are symptoms which point to other imbalances and issues. For most chronically ill, sensitive patients, they've already tried all the diets, protocols, and supplements galore and just keep getting worse. Going after these as individual issues will only harm things further. Look at the roots, not the brown leaves, to find real answers.
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