Science says your gut is your second brain, and the bacteria in there can control your emotions.
Bacteria have been discovered in our guts that depend on one of our brain chemicals for survival.
These bacteria consume GABA, a molecule crucial for calming the brain, and the fact that they gobble it up could help explain why the gut microbiome seems to affect mood.
Massey Uni Senior Bio-molecular lecturer Heather Hendrickson joined Mark Sainsbury, filling in for Paul Henry.
