When did the idea of three meals a day become popular? How often did people eat in historical periods when food was not as widely available?

by Purposeful1

There was an ELI5 post about this a couple weeks ago, but I was thinking it'd be great to get a historian's perspective. Thanks in advance!

rm_wolfe

the faq actually has a section on this.

OldWorldGlory

You might be interested in some threads under the FAQ section entitled "Three meals a day":

Did early humans eat 3 meals a day? When/where did to tradition of eating 3 meals a day start? - 120 comments, over 1 year old.
The first top comment mainly addresses Western Europe, but comments lower down talk about Poland and Polynesia amongst others.
When did having three meals a day--breakfast, lunch, and dinner--become the norm? - 5 comments, over 2 years old.
The comments in this thread focus on disputing the commonness of "three meals a day" even in modern times.
When did the concept of breakfast, lunch, and dinner become integrated into society? - 4 comments, over 2 years old.
The top level comments here go into class distinctions which influence meal numbers and meal times.