Why Do We Get “Butterflies” in Our Stomach?

You Should Know: The term “butterflies in the stomach” is an apt description of the fluttery, jittery, borderline-nauseated feeling we get before a job interview or when we’re falling in love. But what exactly are those “butterflies”? And why do we get them?

Going Deeper: Butterflies happen for a few reasons. The cause of the butterflies can trigger a sudden surge of hormones (like cortisol, norepinephrine, or dopamine), which can affect our stomachs. When we’re worried or nervous, that stress can trigger the sympathetic nervous system — a.k.a. “fight or flight” mode. Various physiological changes occur so the body can focus on either fighting or fleeing, including temporarily slowing digestion and reducing blood flow to the gut. That pause could also contribute to those fluttery feelings. 

Takeaway: Our brains and bellies have a close relationship, known as the gut-brain axis. In fact, we have a second “brain” hidden deeply in the walls of our digestive tract called the enteric nervous system that communicates with the brain in our head via the vagus nerve. 
 
Bottom Line: Thoughts that start in our head can manifest in our stomach as butterflies (or “gut feelings,” too). Breathing exercises, meditation, or relaxing our muscles can help them fly away.