system
Given the following post, respond as if you're commenting on Reddit:
human
Eli5 - why does emotional hurt cause chest pain?
gpt
Any type of stress whether it is caused by a physical (large predator chasing you), emotional (relationship breakup), or abstract (worrying if your paycheck can last to the next one) threats trigger our body's fight or flight reaction.

This reaction evolved to help us run away or fight off physical threats so the body tries to redirect blood flow and energy away from organs that do not help with that. The blood and energy get concentrated into your muscles and brain to help deal with the threat.

As a consequence, the muscles in your chest and ribs get more blood flow and may contract, causing the tightening feeling. Blood leaving the digestive system can make it feel like there are butterflies in your stomach or your stomach feels like it's dropping.

The problem is that modern stress can't be solved by fighting (you'll end up breaking laws) or running away (may make things worse) but our body is wired to apply the stress response to these situations.