be off one's food
to lose one's appetite due to being physically or mentally ill
What is the origin of the idiom "be off one's food" and when to use it?
"Be off one's food" is a commonly used idiom with no specific origin. It has developed over time as a way to describe a temporary loss of appetite or a decreased interest in eating. It is used to describe a situation where someone is experiencing a reduced desire or inability to eat. It suggests a lack of appetite, which can be due to various factors such as illness, stress, or emotional state.