Survival Hydration:
Minimum Water Requirements

The Science Behind Minimum Hydration Needs

Survival hydration refers to times when there is limited water available, possibly for extended periods of time. We are constantly looking for information and understanding on the minimum daily water requirements for survival.

When there is a shortage of water, when our survival is at stake, then the answer as to how to use the limited available water becomes more critical.

Warning: This is not to be tried or tested. This is only in a worse case scenario option. It is a theory to file away in case you should ever be faced with a situation where you may be faced with little water for several days. We are currently looking for actual research. Do not try this on your own without a doctor to monitor you.

Survival hydration science exists but it is not readily available. There does not seem to be a composite collection of research on the topic of how to survive with limited water supplies.

The answers provided here on the topic of survival hydration are within the framework of..... what do we think, what do we know and what can we prove. No one book had all the information. After considerable (and ongoing) research, we propose a new paradigm in survival hydration.

There are few hard and fast rules other than the preservation mode trigger mentioned later. Each of our body's needs are unique. Our survival needs could likewise be varied. This is for adults and not children. Children are not smaller versions of us. They have unique needs.

Actual clinical trials need to be conducted to know for sure the accuracy of what we are proposing here.

Some of the information following is based on the book: The Biology of Human Survival: Life and Death in Extreme Environments
--by Claude A Piantadosi, M.D.

The Body's Minimum Daily Water Requirement

Determining the minimum water requirement for humans to avoid dehydration is based on several factors.

The most basic way to measure need is based on how much water goes out of our body. We need to replace what we lose. This number can be manipulated by using a trigger to initiate survival mode, discussed later.

Generally speaking...
we lose about 600 ml per day in urine
we lose about 400 ml through our skin
we lose about 200 ml through breathing

These numbers are the baseline requirements. Working in the heat, when participating in sports or exercising, the baseline need of water increases. Thus in a survival situation, any factors that require exertion would likewise tax the water stores inside our body.

With the possibility of urine output dropping to 500 ml, the minimum could be just over 1 liter a day or for the sake of making it easy to understand, this would be just over 32 ounces a day for a 154 lb man (70 kg).

Survival Hydration:
Minimum Daily Water Requirement

What Do We Know:
Baseline Minimum Daily Water Need: 32 Ounces

The 32 ounce number from the above book is based on a 154 lb (70 KG) man. As this amount does not allow for any activity that would increase water loss, the amount is thus considered unrealistic. This is at a ratio of 5:1 or 20% body weight in ounces of water. Note this is far less than the recommended intake of 10% of our body weight in ounces 5 times a day which Dr. Batmanghelidj recommended as a daily minimum. It is the equivalent of only 40% of our ideal water intake.

What Do We Think:
The 20% Body Weight in Ounces Can Apply to Weight.

Based on "The Biology of Human Survival" and our own research, we think that as people increase in weight, they will have an increased need, following the same percentages. This may also prove to be fat vs muscle weight dependent. Further research is needed to understand this.

How to Drink in a Survival Hydration setting:
Sips All Day vs Drinking it All

What Do We Think:
Do not nurse the water through the day. Divide the daily ration into 4 or 6. Then drink the entire 4 hour or 6 hour dose of your daily ration. Do not drink it in sips. The reason, the way our body uses and stores water quite efficiently.

Ideally the amount needs to be large enough to trigger the body processes but small enough that the body does not think the drought is over.

Especially important, do not drink your entire days ration in one sitting, so that your body does not think the drought is over and begins to shed rather than conserve water.

Ideally when dehydrated do not drink water without dissolving salt in your mouth first. This allows the body to retain or store the water within the cells.

Yes, our body stores water. This ability is especially critical in survival hydration.

It is better to store the 3 or 6 hour portion of the day's ration of water inside our bodies rather than carry it with us.

See example below.

What Do We Know:
We have 2 oceans of water in our body. One inside and one outside the cells. About 1/3 of your total body weight in water is in the space outside the cells (called interstitial spaces). This water is in the blood veins and arteries, lymphatic system, the fluid between cells, the fluids we secrete inside our bodies and the water trapped in our bones, cartilage, tendons and ligaments.

In dehydration, the extra cellular fluid decreases as the body looses water and sodium. In order to replace water loss from sweat, simply drinking water is not enough. We need to take an appropriate amount of salt with the water in order for it to attain proper osmolarity.

When dehydration happens the body responds in two ways.

1) The water is redistributed so that it is shared by the two oceans.

2) The body goes into conservation mode or self preservation mode.

What Do We Think:
The Preservation Trigger

To start the preservation mode, on becoming aware that the water will be scarce, stop drinking for a period of 24 hours. No water consumption at all during this period will reset the body and slow down the loss. Then on resuming water consumption, follow the rationing schedule of dividing the daily dose (20% body weight in ounces) divided into 3 or 6 hour rations.

This will instantly cause the kidneys to start concentrating the urine and conserve the water we do have.

Clues to this can be found in 1922 coal mining in England. A syndrome was noted in the deep earth miners where they experienced fatigue, muscle cramps and disorientation. Some had epileptic like convulsions. The discovery was called water poisoning.

It was correct in that they were drinking water but not replacing the salt.

By maintaining the rationing, the body will maintain the low intake.

How Much Salt?

What Do We Think:
We simply do not know. We suppose that the salt requirement would be decreased from the 1/8 tsp dissolved in the mouth per 16 ounces of water ratio. But we do not yet know.

Example:
You have 1 gallon of water (128 ounces). It needs to last 5 days. You do not drink the first day. Day two, you divide the days ration of 32 ounces into 4 portions of 8 ounces. On awaking, you take less than 1/16th tsp of salt and dissolve in your mouth. Then you drink the entire 8 ounces within the next few minutes. Holding it in your mouth as long as you can before swallowing it.

The same is repeated with the other three quarts of water.

We are currently in ongoing research on this topic and trying to find the answer among the greatest minds regarding hydration.

Anyone who have knowledge of research on this topic, please share with our community through our contact page.

The Water Cures Protocol not only makes the most sense, it is very similar to what doctors who say not to take salt do with their patients on entering the hospital.

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