The class system, with its fixed mealtimes, stopped us all from getting fat, says Andrew M. Brown. Today we are a nation of all-day munchers — and it showsImagine if, at breakfast, a mother were to offer her family, instead of cornflakes or boiled eggs, slices from a gigantic cake smothered in icing. Would that seem odd? Well, yes, it would: but that’s exactly what a lot of us do — eat cake for breakfast. A muffin is a cake by another name. And on our way to work plenty of us snap up a white chocolate and strawberry muffin, say, from Starbucks, at 583 calories, and wash it down with 300 calories’ worth of warm coffee-flavoured milk. Our readiness to guzzle cake at any time of the day or night, and not only at around four o’clock — the time our ancestors set aside for tea — is a symptom of a wholesale change in behaviour.