>Medieval peasants ate 4000 - 5000 calories per day. As late as the 40s, it was recommended that people eat 3000 calories per day and many men ate 4000 calories

>Medieval peasants ate 4000 - 5000 calories per day. As late as the 40s, it was recommended that people eat 3000 calories per day and many men ate 4000 calories per day. That's the input, but what's the output? If your hypothetical peasant was burning 6000 cal a day, that's very different if they were burning only 1000 cal.