Chronic psychological stress doesn't stay in the mind: through the gut–brain axis it measurably disrupts gut function and microbial balance.
What happens in the mind doesn't stay there: cognitive behavioral therapy echoes along the gut–brain axis and reaches the workings of your gut microbiota.
Anxiety and depression are closely tied to gut microbial balance: the two-way gut–brain axis shapes mood, thinking and emotional resilience alike.
Because most serotonin is made in the gut, antidepressants influence not only mood but also gut motility and the microbial community — and the relationship runs both ways.
In autism, FMT remains investigational: improving gut symptoms is a realistic goal, behavioral change far less certain, and every step is shared with the care team.
In Parkinson's disease, FMT is investigational and most promising early on: constipation eases most reliably, while it complements rather than replaces standard therapy.