system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why does intense hunger sometimes cause nausea? That seems like the opposite of what should happen.
gpt
Because your body is trying to encourage you to eat! Here are the two possibilities I've read about:

According to when you eat, your body will release a hormone called Ghrelin which makes you feel like you're starving, possibly to the point of feeling nauseated. So if you normally eat every four hours and you missed a meal, your stomach starts to release ghrelin whether you need food or not because you've trained it on a schedule. Ghrelin normally stops being released after 30-60 minutes so it doesn't impact you actually getting food and that feeling of nausea will go away.

It could also be low blood sugar! Your body could be releasing the hormone, Glucagon, which can cause nausea. If your diet is higher in refined carbohydrates, you're not used to burning fat because you have more sugars in your diet. If those sugars run out, your body starts to burn fat and this might cause a dip in your energy levels, headaches and nausea.