Gelsomina,
Mt. Whitney is nothing more than a 22-mile, +6,100' day hike. People have a tendency to over think it. It's just a a longer day hike going to a higher elevation than you normally do. It has only a few different requirements, none of them have to do with food and water...other than taking more than you usually take up the trail. I take a balanced approach protein, fat and both simple and complex carbohydrates because you are going to be on the trail upward to 18 hours...if things go as planned. Also, if you do not like the food you are taking at sea level, I can guarantee you, you will balk at it above 12,000'. I also plan to walk off the trail with between 1,000 and 2,000 calories in my pack.
As for hydration, I will take enough Cytomax powder for a couple of liters.
Everything is just a little more than I would take on a day hike in the local mountain of SoCal.
The only thing I am religious about is clothing. I will not go up the trail without enough clothing to make it through the night at 14,500', if something happens.
All this makes for a not so light pack...especially with 8 lbs of water for the Trail Camp round trip.
