While I'm not a diehard doomsday prepper, I prep for things like natural disaster, economic depression, &c. Prepping is also useful for personal situations like a job loss. Imagine you were fired and you have 6 months of foods in your pantry.
When it comes to prepping,
Mormon guides like this are usually good. I don't know the specific historical context, but it seems that Mormons are mostly well prepared because of their history.
Speaking of Mormons, there is Mormon basic 4:
1. Wheat: 200-365 pounds per person per year
2. Powdered Milk: 60-100 pounds per person per year
3. Sugar or Honey: 35-100 pounds per person per year
4. Salt: 1-12 pounds per person per year
Powdered Milk keeps 1-5 years.
Others keep indefinitely.
More Salt if you will preserve foods.
+ vitamin, mineral, fat should be added.
This diet is not good but at least it will keep you alive.