Flour better than rice?

I am a Chinese and Beijing Chinese guys are taller than Southern Chinese because nothern china is cold enough to cultivate wheat. And nothern indians taller than southern indians too. So can we conclude wheat makes you taller due to the protein content?? Wholewheat is better than wheat but why is it more expensive when they process it few steps less. Now is wholeweat still better than unpolished rice?? Or is it the supermarkets are greedy and the middleman is greedy for jacking up the price because it is "health food". You get more weight because you don't remove things from the grain and few less step to process it. Any one can explain this??