Your gut bacteria influence your mood and decisions

Trillions of microorganisms in your gut, collectively called the gut microbiome, do more than just digest food. They communicate directly with your brain through a two-way street known as the gut-brain axis. These tiny residents produce crucial neurotransmitters like serotonin—with about 90% of your body's supply originating in the gut—and impact inflammation, both of which are vital for mental health.