Basically there are four primary food areas:
Wheat and barley based: Mediterranean
Rice and millet based (no gluten): Far East
Quinoa based (no gluten): Andean America
Amaranth (no gluten): Mexoamerica

This gives you a clue as to those areas which are good for you and those that aren't, for example North Africa is a wheat area also with cous-cous (another no-no), for some reason Spain is quite good (paella is rice-based; tortilla omelette is fine; salads and grilled or poached fish;)

(Wild rice is actually a grass so is a 'no-no')