"eat sugar all day and laze around"

I've been following that regimen lately and am 5'10"/5'11" and 130 pounds. I am 19 years old though, there are probably a lot of people my age who manage the same trick. I've noticed there seem to be a lot more >6'1" skinny guys than <6'1". I'm not sure if that's just 'cuz better general genetic fitness, specializing in attractiveness, the mechanics of anatomy, halo effect, not-necessarily-genetic racial differences, and/or many other possible factors.