If it's just for a few days, even a couple of weeks, it's probably not a big issue.
if there's some major emotional episode, or something that should have been a major emotional episode, around when you stopped being hungry, it's potentially the onset of an eating disorder.
If it keeps up more than a couple weeks, please get it checked out. . . could be stomach cancer, or overtraining if you were an athlete, or any of a wide variety of things, some of which are bad.
good luck with that. .
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And if I die before I learn to speak
will money pay for all the days I lived awake but half asleep