What Else Disrupts the Gut
Artificial sweeteners and other overlooked factors
Beyond diet composition and antibiotics, a few other everyday factors have a genuine, evidenced effect on the gut microbiome worth knowing about.
Artificial Sweeteners
A landmark study found that several commonly used non-caloric artificial sweeteners — specifically saccharin, sucralose, and aspartame — altered gut microbiota composition and drove glucose intolerance in mice, with the effect transferable to other mice via faecal transplant from sweetener-exposed mice, and with some supporting evidence from a smaller human cohort within the same study[7]. It's worth being precise about the evidence tier here: the strongest, most mechanistically detailed findings are from animal models, with human evidence still more limited — a reasonable, honest takeaway is that the association is worth taking as a genuine caution (particularly for saccharin and sucralose specifically) rather than as definitively proven at the same evidence tier as the fermented-food or fibre-diversity findings covered earlier.
Other Everyday Factors
Chronic stress disrupts gut function and microbiome composition through the gut-brain axis covered in Section 4.
Poor sleep is independently associated with reduced microbiome diversity, and the relationship likely runs both ways — disrupted sleep affects gut bacteria, and gut disruption can affect sleep quality in turn.
Everyday signs your gut microbiome may be out of balance include ongoing bloating, irregular bowel habits, and unusual food cravings — worth noticing even before symptoms are severe enough to warrant the formal diagnostic evaluation covered next, in Section 8.
A diet heavy in ultra-processed food and low in fibre diversity tends to support a less diverse microbiome by the same mechanism covered in Section 3 — narrow fibre inputs support a narrower bacterial community.
Section takeaway
Artificial sweeteners, chronic stress, poor sleep, and low dietary diversity all have a genuine, evidenced (if in some cases still-developing) connection to gut disruption — worth being aware of alongside the more heavily emphasised fermented-food and fibre-diversity habits.