For Perilous Journey in particular you may just not be able to make the move. If you've got close to enough rations then you can make it, but expect trouble from the GM.
Remember, the GM is there to portray the world realistically. If that means you get Sick(ly) from not eating, that's what happens. By "hard move" I'm really saying that you're asking for trouble, not from a person (the GM), but from the world basically. It's like setting out on a three day hike with only a granola bar. Good luck!