system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: When did some foods become associated with meal-times, and why? Example: eggs, bacon for breakfast.

As the title says, when did certain types of food become associated with eating at certain times of day? When did steak become associated with dinner, for example? When did soup become a lunch meal, as opposed to a hot breakfast dish? Etc, etc. 

EDIT: Thanks for the responses. I'm now going to eat eggs and bacon because eggs and bacon.
gpt
Time needed for preparation. Eggs take a little bit of time to cook, so they're a breakfast food. Something like lasagna takes longer to cook, so it's a dinner food.

There's another factor, too. Back in the early second millennium, breakfast was seen as a necessary evil, and the sign of either a glutton or a working peasant. Seeing as peasants were more common than gluttons, breakfast was mostly a way to get the energy they needed for their work. Food that was high in quick energy took priority.