10/21/2025
IBS isn’t one disease — it’s a collection of upstream dysfunctions that converge into similar symptoms. For some people the root cause is altered transit time (too fast or too slow), which changes motility patterns and sets the stage for fermentation and bloating. For others it’s visceral hypersensitivity, where the enteric nervous system amplifies pain signaling even when structure is normal. A large subset has SIBO or dysbiosis, where microbes are in the wrong location or wrong ratio, driving inflammation and gas production. And for many, the real problem is intestinal permeability, where a compromised gut barrier allows antigen exposure that activates the immune system and increases reactivity to foods that were previously tolerated. These factors stack; IBS is essentially a probability model — once enough physiologic stressors accumulate, symptoms express. That’s why symptomatic treatment rarely creates lasting change. Durable improvement comes from identifying which of these upstream systems is actually driving the dysfunction.