i think they're using 'holiday' in the british sense (to mean 'vacation') rather than the american sense ('  ff9  over the thanksgiving and christmas holiday season'). overindulging during the holidays when there's all kinds of cool seasonal treats is one thing, but gaining weight while you're on vacation for 2 weeks is insane. about 5 years ago i put on 5 pounds between halloween and new year's (a big deal because i'm short) and now i'm super careful. i can't even imagining gaining that in a few weeks!