squidpants

so i was thinking: the phrase "eat your heart out" doesn't make any sense. i mean, since when does being embarassed or have somebody do better than you make somebody want to eat their heart? "gee, you are a better actor than I am, I'd better tear my heart out and eat it, rather than work to become a better actor," or whatever. but then again, the only place i ever see this phrase is in the news, as a headline or some kind of catchphrase.

I found this "origin" on a site that has origins of different idioms, but I am not convinced.

Heart is also defined as the central, core, or inner most part of an object (or person). To eat the heart out is to remove the core or most important part, a part that will surely be missed.
The phrase is probably a shortened way of saying "This will eat your heart out".
Alternatively,
Adapted from the 16th century "eat one's own heart", meaning to suffer from silent grief or vexation. It also has roots in the Biblical phrase, "to eat one’s own flesh", used to describe an indolent person.
Thanks to Mike Pierce

(http://members.aol.com/MorelandC/HaveOrigins.htm)