What is the origin of the idiom "food for thought" and when to use it?

The idiom "food for thought" originated from the idea that just as food nourishes the body, certain ideas or information can nourish and stimulate the mind. It emphasizes the idea of providing mental nourishment or intellectual stimulation through thought-provoking or interesting content. The phrase is often used to suggest that the information or ideas offered are worthy of contemplation and can contribute to personal growth or deep thinking.