Biology
Microbiome–Gut–Brain Axis Modulation in Major Depressive Disorder
Quick fact
About 90% of your body's serotonin—a mood-regulating neurotransmitter—is produced in the gut, not the brain.
Why this is interesting
Have you ever felt 'butterflies' in your stomach when nervous? That's your gut-brain axis at work—and it might hold the key to understanding and treating depression.