> here are the amount of calories that some of these foods provide for $1 The glycemic index shows that calories are worth little if they blow your blood sugar

> here are the amount of calories that some of these foods provide for $1 The glycemic index shows that calories are worth little if they blow your blood sugar through the roof and then send it crashing as flour-derived food stuffs usually do. Roots and tubers contain more complex carbohydrates and have a lower GI, providing energy over a longer period. That said I agree with the spoilage part - grains do last longer before spoiling. > The cited expert is also wrong, if I'm not mistaken, about the lack of civilizations born of on a staple other than cereal grains. The New World civilizations (Aztec, Inca, Mayas) did not have access to cereal grains. Their primary staples were potatoes (South America) and corn (Central America). The author wasn't talking about civilisations, they specifically mentioned states, which I guess could be translated as empire or collection of civilisations taxed by a central authority. That said I have no idea whether their point was correct - I just thought it was interesting.