system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why it's dangerous for extremely malnourished/starved people to over eat when reintroduced to food?
gpt
Digestion takes a fair bit of energy to do, especially if you haven’t eaten anything recently (since it needs to restart a bunch of processes, make stomach acid, etc.). You get back more in the long run, obviously, but it takes energy to break everything down so you can use it in the first place.

For a person who is right on the verge of death, that initial amount of energy required can be enough to push them over the edge and send them into shock and death, so you need to be careful when first feeding someone who has been starving.