In a lot of those civilizations, diet for most people wasn't that good at all, and grain was traded like a currency. In Japan there is this myth that the nation thrived on rice. In fact, much of the nation periodically starved, rice was like gold, and most people grew rice for their overlords and lived a subsistence diet of cabbage, buckwheat (a seed, not a cereal grain), beans, and what fish and shellfish they could take from estuary systems before modern development rendered them polluted and fished out.
My point was not to swap dietary stories about how skinny you or I are but to point out that in this modern world carbohydrates are too much of a good thing--we don't physically work to earn them and we binge on them when we can get them (which is all the time now).
I'll take brown rice over white rice, but I still cut back on the amount and I'd rather have a grilled fish, some fresh tofu (ahh, the tofu in Japan is so good), and some veggies, thank you. If you lead a fairly sedentary life--and most do nowadays--protein, some fat (olive oil and even some butter), and veggies and you can't go wrong.
Charles J
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