What bothers me about these people that claim to not require eating is that they have been tested time and time again, and each time they either begin to show the strain, or they attempt to cheat.
It'd be highly interesting if any of them are actually genuine, of course.

Info: There are a variety of groups of non-eaters, the breatharians being the most well known. Others involve eg. sucking up the sun's rays instead of food. James Randi (the skeptic/magician with the $1mil challenge) has tested a couple of them and found them lacking so far.