I love seeing articles that talk about the nutritional balance in diet. Paul B.’s “Staple Foods Storage By The Numbers” is a good start, but I want to jump on and point out a few more details.
Daily caloric intake recommendations depend heavily on activity. Yes, the recommendation is 2,000 calories for an adult male with moderate activity (note - *not* exercise!), and 3,000 us reasonable in a survival situation given the need for hunting, planting, building infrastructures and defenses as well as defending. However, if your plan is simply to hunker down and depend on your stocked resources, 1,500 calories is a better recommendation for adult males, 1,200 for females. Children to age 10 or 11 need about 1,200 calories, regardless of activity level, teens generally need the same intake as adults, but add an additional 25-40% more calories for moderate to heavy exertion.
On the other hand, if you plan to have to walk or hike your way to a secure site, and are planning on a 3-4 mile pace for more than 8 hours a day, even 3,000 calories will not be enough.
The type of exertion also alters the percentages given in Paul B.’s article. Sedentary or low exertion requires lower calories and a higher ration of protein to fats and carbs. The reason is that protein digests and is converted to energy by the body at a much slower rate than carbs. Keep the fats down to 20%, boost protein to 40%, and stick to 40% (or less) carbs. High exertion levels require different food choices at different times of day – carbs in the morning, protein and fats at night. The more you exert yourself, the more muscles need to be repaired. Carbs are burnt fairly fast, but then the body converts stored fat and protein to energy – that needs to be replaced. Extreme exertion requires a diet that is 30% fats, 50% protein, and 20% carbs! Think marathon runner and triathlete levels of exertion – but if you’re working 16 hours a day gathering firewood, hauling water, hunting, tilling, plowing – you’re going to be burning muscle if you don’t replace it.