Interesting fact: McD burger buns are made from not just corn flour, but it also has a very low density and is very airy.
Why? Apart from low cost, it's because when you've chewed it and your stomach is churning it before digestion, it collapses to a very small volume.
Low foodstuff volume means that its ability to satiate hunger is low and very brief. It may taste good, but you'll be wanting a second serving in short orfer.
#diet