Can a few deep breaths really help calm down your stress level? Absolutely. And scientists have even studied how it works… Deep abdominal breathing stimulates the vagus nerve, which runs from your brain stem down through your abdomen. This is the main nerve of the relaxation response. Once stimulated, the vagus activates a chemical compound called acetylcholine–a neurotransmitter that reduces inflammation and sends messages from your brain throughout your body. And the messages all say, “Relax.” As an added bonus, new research shows that the stimulated vagus nerve also activates stem cells that actually repair brain tissue damaged by inflammation. All of that, just from taking deep breaths.