Figuring out how much food to bring on a hike is easy, once you know how many calories you need. If you get into town with too much food, you know to lower your calories per day and if you get into town hungry, you can bump it up. You will at least know how many calories you get each day, so you can ration your food.
I usually figure 1500 in the begining of a hike and move it up to about 3000 once my appetite kicks in. But I can always ration it, to make it last longer if I slow down, or eat more if I’m going faster. Some hikers needed 4000 -5000 calories, some only needed 1500, even after being on the trail along time.
When I arrived at the begining of the PCT (Pacific Crest Trail), my food bag contained: 2 apples and 3 bars. When I got to the Lake Morena store, 20 miles later, it still had an apple and a bar in it.
To get through a 200 mile section of the Sierras, I bought a basket of food, sat down, and added up the calories as I loaded my bear canister. I filled a Bear Vault 350 with 20,000 calories, figuring that would be 2500 calories a day for eight days. I then brought some extra food, in my food bag, for my first day. That gave me an extra day of food in case I needed to slow down. I got into town 8 days later with nothing but some really bad trail bars rattling around in my bear canister. I was hungry when I got there, but it was a good, edgy hunger, not a debilitating hunger.
Some people quit because they can’t carry enough food. I think they would find, if they slowed downed their pace a little but upped the hours that they hike, they could still hike the same miles per day but would require less food.
