Tryptophan

The gut-brain serotonin pathway is the mechanism behind mood swings, anxiety, and brain fog that start in your digestive system.

The tryptophan-serotonin pathway your gut bacteria run — and what happens when it stops working.

SSRIs don’t work for half of depressed patients. The reason might start in your gut, not your brain.

Your body needs tryptophan to make serotonin. But when your gut is inflamed, that tryptophan gets stolen — and the byproducts are worse than low mood.