Read Andrew Skurka's site as well (link posted under Really Really Long Hike).

His diet is basically Balance Bars (a sponsor) all day and one meal at night.

Personally, I don't see the point of these long unsupported trips. Why not just take a gun or some other weapon and hunt along the way like the pioneers or the Eskimos? Not that you can do that on the AT these days, but you get what I mean. Trying to prove how long you can live off of sports bars seems a bit pointless.

Will Steger and some others have done unsupported trips in the Arctic and Antarctic towing sleds with hundreds of pounds of food and gear. Same idea, different environment.