Tryptophan

New research reveals how oral bacteria hijack your gut’s tryptophan metabolism through the kynurenine pathway — and it changes everything about the gut-brain connection.

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

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

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.