I'm trying to figure out if there's more than just tradition to the advice to eat three meals a day. Is the advice valid? Does it come from reliable sources?
closed as off topic by Greg♦ Nov 19 '12 at 18:51
Questions on Physical Fitness Stack Exchange are expected to relate to physical fitness within the scope defined in the FAQ. Consider editing the question or leaving comments for improvement if you believe the question can be reworded to fit within the scope. Read more about closed questions here.
It's a conspiracy.
Most people eat how they eat because of culture: it's how they were raised, or it's how their peer group acts.
There are good reasons to eat three times a day, and studies, but these are either exploratory (admitting that the ideal number, size, and composition of meals is unknown, and attempting to obtain data to lessen our collective ignorance) or ex post facto (taking what we already do, and attempting to prove that it's swell).
There are good reasons to eat three times a day, but they're not scientific studies. I'd bet that most people who eat three times a day do so for practical or social reasons: that's when they get a break from work, that's when it's socially acceptable, that's when it's expected, and...it's convenient to eat a few large meals, and I get hungry if I eat fewer than three meals in a day.
The BBC sheds some light on the history of the three-meals-a-day mindset:
The article jumps around a bit, but the end result is clear: economics and the vagaries of culture and history have much more effect on when the majority of people people eat meals.