serotonin
gut health
microbiome
Serotonin Is Made in the Gut: Rethinking Mood at Its Source
Roughly 90% of the serotonin in your body is produced in the intestinal wall, not the brain. That single fact reorganizes the way we should think about mood, digestion, and the treatments that actually work.
By UltraSkool Research Team
May 14, 2026