The vagus nerve is a cranial nerve that activates the parasympathetic nervous system and increases levels of oxytocin and the calming neurotransmitter acetylcholine. Supporting the vagus nerve and thereby improving parasympathetic tone promotes relaxation, sleep, digestion, and healing.
Activating the parasympathetic nervous system dials down the sympathetic nervous system or fight-or-flight response. In that way, the vagus nerve acts as a built-in “stress-reset button.”