Nutrition demands in the mountains are extreme.  Add factors like a heavy pack, varying terrain type, heat, weather, smoke, and you can wind up with nutrition needs that seem more like the calculation for an atoms potential than a calorie calculation.    Luckily for us, Dr. Brent Ruby spent more than 25 years studying this to help us understand exactly how it works.  He joints us for two parts- one on nutrition (this one) and the physical demands and training for such tasks in part 2.     Links Dr. Brent Ruby.  Summary of Dr. Ruby's Research  Access to our F+ Cohort Sign Up Managing [Nutrition] Extremes in Hostile Mountain Environments Article