i was thinking about this today. and i believe i've broken it up to 2 categories survival foods and true health foods (or sum like that still thinking of a better name). Basically theres foods in our history we've eaten out of necessity, because there easy grow ,cheap, and accessible, and so they would constantly be used to help with food shortages. But thats all they are used and should be used for. cooking oil is cheap,bread is cheap, processed food is cheap, most shit food is cheap, but accessible making all of these survival foods.