A girl I know gave up chocolate. However, healthy stuff with chocolate on it is negotiable.
There's a girl at work who gave up chocolate...but only "solid chocolate".
On the other end of the spectrum, my Maronite in-laws give up all animal products along with caffeine, alcohol, sex, etc. They're basically brown vegan Mormon nuns for two months (b/c for some reason their lent is longer than normal lent).