This episode is an example why I like The Simpsons so much.
The main plot: Milhouse is falling in love with a girl who just moved to Springfield. He's hanging out with her all the time and neglecting his friendship with Bart.
The subplot: Lisa is afraid Homer will get fatter and fatter and eventually die from his obesity. So she decides to order a cassette that subliminally helps you lose weight while you're sleeping.
Favorite scene: When Homer watches 'Smartline' (hosted by Kent Brockman) you see a report on obesity in the USA. Then you see stereotypical 'fat & happy' Americans: Don DeLuise, Santa Claus.
Then there is a dramatization of what kind of diseases Santa would have when he'd be a real person. You see him lying in the hospital with the reindeers standing next to him crying and Kent Brockman narrating: "If Santa was alive he would have to deal with kidney stones, hard breathing, and impotence." Then, the doctors are loading the defibrillator and trying to reanimate him.