system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why won’t your body allow you to do things like hold your breath too long, but you can ingest enough alcohol to poison yourself or overeat?
gpt
Overeating is a very new concept.  Until recently, there was not a constant surplus of food for most people.   Your body wants you to overeat, because it expects there to be a famine or food shortage at any moment.

Your body will stop you from drinking too much alcohol if it can - that is why you start to vomit.   The problem is that when you drink, it has to go down your throat and into your stomach, then into your small intestine and be absorbed into your blood.   By the time your body knows there is a problem, you might have done a dozen more shots.   This lag is what lets a person poison themselves if they’re quick on the draw.