Check out this site. Here's one of the posts:
Originally Posted by whitetail
I'll throw in a curve ball. I contend that the phrase, "I'm so hungry I could eat a horse" gained is popularity from the history of those on long journeys as a last resort, actually eating the horse that they needed for travel in order to survive periods of starvation. I think its origin therefore, probably had less to do with the size, or the social taboo of eating horse, but the idea that eating horse has been, historically, a signal of last resort before starvation.
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posted by allthewhile
at 2:35 PM
on November 19, 2006