According to Dr Elliott, this sensation is triggered by the nervous system governing our fight-or-flight response. He explained how stressful moments can trigger the release of the hormone adrenaline, increasing our heart rate to pump blood away from our gut and into areas such as the legs.
He said: “This shortage of blood to the gut slows digestion. The blood vessels in the muscles around the stomach and intestine constrict. This produces the ‘butterflies’ in the pit of your stomach.
“In fact it’s the gut lower down sensing this shortage of blood and oxygen and the sensory nerves are letting us know it’s not happy with the situation.”