Originally Posted by
GoldenBear
On my first real backpacking trip, I ended the day at RPH Shelter, a place where a local pizza shop will deliver very close to -- it even has its menu in the shelter. A few real backpackers were ordering typical huge meals, and asked me if I wanted to order anything. I literally got nauseous at the thought of eating pizza, despite decades of enjoying it -- indeed, I found that I didn't want to eat ANYTHING.
I asked some of these backpackers why this might be so, and their basic explanation was that most people* don't eat because they're actually hungry, they eat because they're bored, or it's time to eat, or it's a social event. When you're backpacking, at the end of the day you're invariably too tired to care about any of these things -- you just want to rest. Your body uses up your fat reserves for survival, and basically "tells" you, "Just let me rest -- I don't need any food, so let's just skip that, okay?"
They also noted that this reaction lasts for about five to seven days, at which point you've burned through your reserves, and your body starts to tells you, "Eat, eat, eat!!"
A friend of mine who's an M.D. later explained that, under the above circumstances, all of your body's energy is going into repairing itself, and the digestive system gets a lot less attention. As you're getting enough energy from your fat reserves, your digestive system basically says, "Hey, don't bother -- we're okay, and other parts of your body need more work, anyway."
With this knowledge, I have learned to plan for eating very little for several days at the start of a backpack. Fluids, yes; salt and electrolytes, yes; but food, not much. I've found it works just fine, saving me weight, space, and food prep time. I'll get to my end point, set up my sleeping arrangements, fill up my water bladder, eat some protein, and collapse.
* I'll add a disclaimer that they meant, "people who have enough money and free time to go backpacking."