Watch "Shallow Hal"
It's hilarious....
Now, the reality is most guys perceive that mating with a fat chick brings on fat offsprings (despite what the truth may be) ...... Fat children aren't exactly a sign of health.... since obesity leads to many diseases in life...
If the fat chick looses weight like on those jenny craig ads etc... then their perceptions changes....
Most guys are inherently superficial....
Now society thru the mass media has bombarded us with images of what attractive is like.... eg. naomi campbell, nicole (whatshername), all the chicks in present playboy, all the chick in other tasteful gentlemens magazines....
I gotta say, I'm a sucker for the mass media.... I'm just getting with the program!!!