[btilly]

It should be common knowledge now that too much of any one thing will kill you

Not potatoes. You can live on nothing but potatoes and water and you'll be healthy. You'll likely get very bored of the diet, but you won't be missing anything essential.

This is true of very few foods.

(This is something that I learned when my wife was studying for general physiology.)

[gxs]

Your comment seemed interesting and made me look it up.

According to the straight dope, not quite, but almost:

http://www.straightdope.com/columns/read/2828/could-i-surviv...

[silentbicycle]

You have to eat the skins, though. And it helps if you're doing manual labor (and occasional supplements of buttermilk, kale, oatmeal, etc. will go a long way).

There's a great essay about surviving on potatoes in John Thorne's _Pot on the Fire_, also an excellent cookbook.

[eru]

Fresh (breast?) milk or eggs would probably also work at least as good?