Hi, I've just purchased a emergency ration. Total Kcal: 2500. It's devided into 18 bars, so that would be about 139 Kcal a bar.
The packaging says:'' Do not consume more that 6 bars in 24 hours''. So in 24 hours you would have a total of 834 Kcal.
You use a average of about 3200 Kcal a day, so: Is this ration any good? 0r is there something wrong in my calculations and estimates <img src="/images/graemlins/confused.gif" alt="" />

Could just be that they figure it will get you by until you can get to real food. Does it list ingredients? Also fat & fiber amounts?

Please see my edited post on ''How much Kcal in survival rations'

"You use a average of about 3200 Kcal a day...."

I don't use anywhere near that amount, and if I started eating enough to supply that I'd soon need a whole new wardrobe!<img src="/images/graemlins/grin.gif" alt="" /> I use 2000-2200 per day tops, less if I'm sedentary. I think you'll find it will vary widely depending on age, sex, fitness level, etc.

The key is to remeber that this is a "survival" ration. Not a fill your belly holiday meal. it's supposed to be "just enough"
Matt

For my next 100-foot yacht, I think I'll splurge and get some "fill your belly, holiday meal" lifeboat rations. Anyone know where I can get some? <img src="/images/graemlins/grin.gif" alt="" /> Love that choice of words!

Most "survival rations" are designed according to SOLAS / US Coast Guard requirements that stipulate 2400 KCal per person. Some lifeboats built and equipped to older specifications require 3600 KCal rations to replace their original older style rations. That's why these rations are most commonly found in these sizes. The daily ration is based on the assumption that you are not going to be doing much sitting in a crowded life raft. So, a few hundred calories a day will suffice to keep you alive and functional for a short duration survival circumstance.

Humanitarian rations are similar, often just repackaged survival rations, but again assume a very sedentary existence under refugee camp or similar circumstances. Moreover, they assume the refugees in third world countries for which they are designed are used to existing on substantially less than we are used to eating on a daily basis.

Any other use of these rations is beyond their design scope and must be assessed according to your expected requirements. They are not MREs or field rations of any sort and are not in any way designed to do anything but provide subsistence levels of food for an extended duration.

Some of the survival research from WWII revealed that a few hundred calories per day spares protein (ie muscle) breakdown, and will let your body " starve more gracefully".

So 800 calories won't let you keep your weight, but it will spare your muscles from early catabolism.



source
Fluids and Electrolytes in the Surgical Patient 4th ed by Carlos Pestana