The science behind what we eat for breakfast

Our ideas of what qualifies as breakfast food are cultural distinctions, not scientific ones. Breakthroughs, discoveries, and DIY tips sent every weekday. If you live in the United States, there's a good chance you were picturing some combination of eggs, bacon, cereal, and/or pancakes. Of course, we also know that a classic British breakfast consists of beans and fried bread--two savory foods most Americans don't associate with their first meal of the day. Is there a science behind why we think of some foods as breakfast and others as not?