Is it actually useful to ration food?

Question

Is it actually useful to ration food?

What is the difference between eating a little bit of food at an interval and eating enough to be full at once?

I'm getting the same amount of calories/nutrition** regardless of when I consume it, so who cares? Why not just eat whenever you're hungry to the point of satiety?

Is that an overly-simplistic view?

** I suppose there could be a difference in the percentage of nutrients absorbed. If I get too much of a nutrient, perhaps my body will excrete it, so, in that case, it's better to consume it periodically when your body needs it.

The scenario is being stranded somewhere not knowing when rescue will come - so generally no activity.

Answer 1

There are several reasons why I think rationing is useful.

• Morale - If you eat all your food on the first day you won't have anything to look forward to. If you eat a little bit twice a day you can look forward to your next morsel instead of regretting eating all your food. Meals become a break in the monotony and something pleasant you know will be coming. Being able to focus on your next "treat" might be the thing that keeps you from total despair. Also if nothing else it gives you something to do for a few minutes every day...

• Forcing Efficiency - Sure you will put the same amount of calories into your mouth regardless, but your body may not extract the same amount of calories. Unlike water the human body has long term storage capabilities for food/energy. By reducing your calorie intake you force the body to burn those energy reserves, and maximize utilization of the calories you consume. Furthermore this signals to the body that it should hoard its food reserves and seek to maximize the calories it extracts from food.

• Comfort - You can become accustomed to living moderately to mildly calorie deficient. The hunger is always there but it is easy to push it to the background. When you literally don't have anything to feed your body this is much harder. That's why people who truly don't have any food resort to desperate measures like eating dirt cookies.

• Thrive vs Survive - The amount of calories you need to survive is less than the calories you need to thrive. Sure there are generic calorie intake recommendations. This is the recommendation for people to thrive. To meet basic survival needs you need less calories than what you'd need to thrive in the same circumstances.

• Not Everything Is Stored - Read (and up-vote) the two other answers that mention water soluble nutrients and proteins. There are some vital substances that your body has no effective way to store. You need to keep consuming them, even in small quantities, to survive since that is the only way to keep them in your body.

• Accountability - People are great at rationalizing things. If you ration your food you won't end up sliding down that slippery slope where you eat "just one more wafer thin mint" until you run out of food. By having an explicit plan in place you know that you can eat X food per day. Think of this like credit cards. No one forces you to overspend but the temptation is there and clearly a significant number of people succumb to that temptation. Now imagine you're sitting in a cave, hungry with nothing to occupy your time. What are the chances hunger and boredom are going to cause you to rationalize a reason to eat just a little bit more if there is no accountability. The accountability aspect is even more crucial when you're part of a group. This is why setting explicit rations is better than soft metrics like "eat when hungry but not too much."

---

I don't have any official sources to back this up, but I have some experience rationing food. My cousin and I spent several months cycling around Europe with little money and consequently not much food. By the end of the trip I had lost significant weight, but overall the trip was quite enjoyable. It is interesting though when I reflect on my memories food has an unusually strong imprint. Meals that would have been unmemorable normally are seared in my memory. I'm sure that is due to the constant and inescapable hunger. I think if we hadn't rationed, the trip either would have been much shorter, or more driven by hunger during our fasts.

Answer 2

Aside from the previously mentioned micronutrients, your body doesn’t really store protein in any significant way, so in order to ‘repair’ your body you need a relatively constant stream of protein (or rather, amino-acids). Nothing bad happens if you fast for a short while, but it does mean you will obtain amino acids from breaking down your own muscle which will cause issues in the long run. If you would eat all your food at once, you would likely not even use all of the protein for repair but rather convert it to energy (fat). And that is if you could even digest all of it.

Additionally, you can also not store essential fatty acids other than in your stomach after eating. Again, nothing bad happens immediately if you run out but over longer periods it can affect many things such as hormone levels.

The other thing is that your body can only effectively use its own fat reserves if it has some food to initiate the process (that’s the dumbed down version, you can read more on https://en.m.wikipedia.org/wiki/Citric_acid_cycle?wprov=sfti1) If you don’t have food then using your own fat reserves also means breaking down your muscles to initiate the process.

All good reasons to ration food.

Answer 3

There are many nutrients that your body cannot store, or not in decent extra amounts. Water, salt, potassium, vitamin C, etc. You will rapidly excrete these, and then greatly feel the lack of them when you are fasting for days.

Yes, you can to some extent gorge yourself on macronutrients (fat, carbs, protein) because these will be stored as body fat fairly efficiently. However, if you are planning to be functional during your famine, it is no good being overfed for a couple of days then weak with hunger for several more. You can reduce your energy consumption quite considerably from ad libitum levels without feeling unwell. Why do we feel weak when we still have fat stores to draw on? Because it takes time to get into ketosis to fully access those stores, and the process wastes some energy, and in times of famine we have evolved to feel tired so as not to waste energy dancing or whatever.

Answer 4

The simple answer is that yes it does make sense to ration, see the stories of the men who survived the Essex or the Mutiny on the Bounty or the Chilean Miners or many countries during wartime.

From a mathematic point of view, one rations when does not have enough food for the timeframe between now and a resupply. If you eat enough to be full all the time, you will run out of food.

When one is backpacking, one wants to make sure that there will be enough food to finish the trip and while that may not mean eating less than needed, you do want to keep an eye on how much is left to make sure you don't run out.

From my experience backpacking with fewer calories than needed, there are some tricks to make it easier.

• It's easier to sleep on an empty belly than to hike on one.
• Eating your food reduces the weight you carry and will speed you up so don't stop eating.
• It can make sense to speed up the pace, you are going to burn calories regardless of what you do, and getting back to the trailhead in less time reduces the number of calories required.

The short answer here is that if it didn't work, I don't think it would have been used to such an extent historically.

Answer 5

What I've always understood to be the rationale, and doesn't seem to be directly addressed with the other answers, is that the human body adjusts its metabolism to its resources. If you gorge on all your food, you're signalling to your body that there's plenty of food. If you eat only a little bit a day, you signal to your body that it should go into starvation mode. This means not only burning fat reserves as noted in other answers, but also reducing metabolism (note that this means that keeping warm is an important part of survival). This is especially useful in cases like the Chilean miners; there was very little activity they could do to help their rescue. Survival came down simply to staying alive long enough for others to get to them. In a case like that, signalling to your body that minimizing calorie use should be prioritized way above remaining strong and active is going to help your survival chances. On the other hand, if you're in a situation where strenuous physical activity is needed to survive, but you don't have much food, you're in a double bind.

Answer 6

One aspect not discussed much in other responses is that the body actually has a fairly limited capability to process food at all.

Your gut is a conveyor belt that never stops, not a production line where it does each step properly before allowing it to move on. If too much comes through, you can't process all of it before it passes out of you again.

If I eat all the food I need for a week in one sitting, most of it will pass through me only partially digested and critically, won't be edible afterwards, effectively wasting the vast majority of its value. (I'll also probably throw up, but that's pretty much the same result)

An extreme example of course. But to a degree, eating smaller volumes of food at intervals will digest more efficiently simply because your stomach acids and digestive tract have less to deal with and can devote more 'attention' to it.

When you need to stretch your efficiency, you waste food if you eat more than you can properly digest at a time, so consuming less in each sitting will allow you to make better use of each meal and so stretch your reserves for longer.

Answer 7

I think the simplest answer is also the best in this case. This should work for (what I presume is) the majority of rationing cases.

Q: Why are you rationing?

A: Because you do not have enough food and need to survive until you get more. Once you run out of food you will have no option to ration, as then your only choice is to fast.

I think that the "do not have enough food" part is key here to make sure we are on the same page. If you have enough food but are not eating it, then you're dieting, not rationing. Maybe this is not correct given the technical definitions of the words, but I think this fits with most peoples' view of what it means to ration: to limit the use to avoid running out entirely.

If I have 3 days worth of food but I think I might not be able to get any more food for 6 weeks, then the math is simple. I can...

1. eat normally for 3 days (I'll assume 3 square meals per day), then hope that I can go completely without food for 5 weeks and 4 days more without dying, or

2. not eat for a few days (assuming I'm initially healthy, otherwise skip this initial fast), then eat half of what you consider a normal meal once every two days, then hope that you can go completely without food for a few days more without dying.

3 days * 2 times less food per meal * 2 days between eating * 3 times fewer meals per day

= 36 days worth of rationed food instead of 3

Would you rather start a 39 day fast while starting in your normal, healthy state of body or a 3 to 6 day fast in a less healthy, starving state of body? You probably will die in the first scenario since you likely cannot survive 5 and a half weeks of zero nutrition. Yet many people all over the world are used to eating several times less food than you or I every day as a normal part of their lives for their entire life.

If you risk death from having zero food, we are told by the experts (I use that term loosely, but I would rather heed the advice than risk death) that you will die within a few weeks of eating nothing. A few weeks. People do not starve to death from a few weeks of severe malnourishment when they eat a tiny amount, rather, they live long, unhealthy lives for months or years.

Summary

You can stay alive for a long time in an unhealthy state of starvation as long as you keep eating small amounts of food, but once you stop eating altogether (which is what will happen when you run out of food from eating it to soon) the timer to a 100% certain death starts counting since people generally survive only a few weeks without eating anything no matter how much they bulked up first.

So the rationing question becomes this...

Choose one: Do you want certain death in a few weeks, or do you want to live a malnourished, unhealthy life for a lot longer and maybe (or maybe not) die in months or years?

---

Caveat (warning)

If you are do not know how long you will need to ration, you need to make sure you do not over-ration. You can die from starvation even while you are still eating sparingly.

Some people have died from hunger or thirst even when they had more food or water available. They rationed so hard they died before using all their supplies. Please don't die of thirst when you still have water left. How much is the right amount? It's hard to say, and either way is a gamble.

If you are stuck in a dry mine, the middle of Antarctica without a heat source, or in a prison cell after a prison is abandoned, then I am sorry for you. Otherwise, food and water can be procured in the vast majority of locations on Earth, even harsh ones. Ration softly and spend your remaining days as a race to learn to extract food and water from wherever you are.

See also this other outdoors.SE question where the amount of time one can survive with zero food is discussed a bit more.

Answer 8

There are good metabolic reasons to ration; however it would be good to consume food highly susceptible to rot/spoilage or theft by another animal (2 or 4 legged). There would be a significant morale hit if you are rationing tightly only to have what you could have eaten be stolen or go bad.