Medical research has discoverd two virii (AD-36/ SHAM-1), that are now blamed for obesity! It's said that these virii can be contracted via air-passages (breathing or setting next to a fat person!), and like smoking ('passive smoking' makes you 'ill'), passive overeating can get you fat!
Also called 'infectobesity' (infectious obesity).
I ain't fat, so there's no possibility that you can become a passive overeating butterball, Meg! Come'ere pootiepie, teach me how to dance!