There are several factors in play when discussing shelf life and each of these factors can be affected differently.

Minerals
Minerals are the chemical elements you need in order to stay alive (this excludes oxygen, hydrogen, carbon and nitrogen). Minerals are not greatly affected by long-term storage and will still contribute to the total number of calories needed.


Carbohydrates
Carbohydrates are simple sugars and larger molecules including starch and dietary fiber. Carbohydrates are not greatly affected by long-term storage and will still contribute to the total number of calories needed.


Proteins
Proteins are large organic compounds and are essential to life. In long-term storage, proteins can denature and deteriorate in quality but will still contribute to the total number of calories needed.


Vitamins
Vitamins are the nutrients required for essential metabolic reactions. When stored for an extended period of time, vitamins are susceptible to destruction by heat, light, and oxidation.


Fats
Fats are a wide group of compounds that are generally soluble in organic solvents and largely insoluble in water. When stored for long periods of time, fats can acquire off odors and off flavors known as rancidity.