simple reasoning....
the reason why wone room mate gets larger, while the other slimmer is easy....
Observer the following scenario...
Fat & thin do the grocery shopping...
Thin goes out for a typical thin girls night out, ie, lots of booze, sex and drugs = physical movement, sweating and vomiting - all great ways of keeping weight down!!
Thin arrives back home sometime the next mid afternoon and heads to the kitchen... on the way avoiding Fat who has been playing WOW all day/night/day...
Thin makes it finally into the cupboards only to find that the groceries have been converted into a thick layer of crumbs and wrappers on and around FAT...
Fat & Thin then go out grocery shopping
Thin goes out for a typical thin girls night out................................. the cycle continues........
Paris - as thin girls have more co.... er... fun!!!!