When it comes to the hierarchy of survival needs, water is one of your main priorities. You can only survive 3 days without water, and you’ll be weak from dehydration before you reach that point of death.
Because of how important hydration is, there are a lot of myths surrounding drinking urine for survival.
Hopefully you never get to the point where you’re considering drinking your own urine, but here’s what you need to know if you do.
What’s In Urine?
Let’s start with what urine is.
In a healthy person, urine is approximately 95% water.
That’s great, right? We need water for survival.
It is the remaining 5% of urine which is problematic. The kidneys do a great job of filtering impurities from the blood and excreting these through urine. There are over 3,000 compounds in urine which vary depending on what you ate, medications taken, environmental contaminants, and waste metabolites. This is many more compounds than found in other bodily fluids.
But Isn’t Urine Clean?
When someone says that urine is “clean,” they mean that urine doesn’t have much bacteria in it.
Yes, this is true. Unless the person has a kidney infection, urine will generally be very sterile.
However, this still doesn’t make urine safe to drink.
Remember those 3,000+ compounds in urine? The main ones are:
The more dehydrated a person is, the less water is in the water. Thus, the concentration of waste products is higher in urine from dehydrated people.
But What about that Time Bear Grylls Drank His Own Pee?
I personally hate those reality TV stars like Bear Grylls who give bad survival advice or only show extreme situations.
Yes, there are plenty of real cases where people drank their urine to survive:
- The Chinese man trapped under earthquake rubble who survived 6 days by drinking his urine
- In addition to amputating his own arm, Aron Ralston also drank his own urine to survive being trapped under a boulder.
- In Rome, nuns stuck in an elevator survived by praying and drinking urine.
Let’s be clear that these are EXTREME survival situations. In most cases, you probably have a source of water available to you (even if you don’t realize it).
For example, consider these ways of finding water in the wilderness which include methods like collecting dew and following ants.
What Happens When You Drink Urine
Your kidneys filter waste products into urine. When you drink urine, you are putting all of this waste back into your body – much of which will end up back in your kidneys.
This puts a serious strain on your kidneys, which is why Slate reports that drinking urine can cause symptoms similar to kidney failure.
If you have suffered a crushing injury, then drinking urine will be even more dangerous. Damaged muscle fiber cells leak potassium and phosphorous into the blood. The kidneys already will have a hard time clearing these. Someone drinking urine would put even more strain on the kidneys.
The Summit Register goes as far as saying that drinking urine will not rehydrate you. Rather, they say it will dehydrate you at a faster rate because of all the pollutants and sodium in urine.
Urine Therapy Side Note
In case you didn’t know, apparently there is a new trend called urotherapy where people drink their own urine. Apparently a lot of people think that drinking urine can treat cancer.
There is very little research showing that drinking urine has any medical benefits. Even if research does show benefits, bear in mind that this is urine of hydrated people so the concentrations of waste products is much lower!
How Long Can You Survive By Drinking Urine?
Remember that the waste products in your urine will become increasingly more concentrated the more dehydrated you become.
We also lose a lot of water through sweat, so you will lose a lot of the water which actually was in the urine.
The first time you drink your urine for survival, it might have a higher percentage of water in it. The next time, the urine color will be darker because it is highly-concentrated with waste products. You are basically doomed to choose between dehydration and renal failure.
There is a lot of conflicting advice on exactly how long you can survive by drinking urine. The general consensus is:
- Drinking urine will give you an extra day or two of survival.
- You can drink urine 1-3 times before it becomes too concentrated.
Can You Purify Urine to Make It Safe for Drinking?
Yes! Purification is how the astronauts drink urine safely in space. You probably don't have access to NASA's filtration methods though. So, the best way to purify urine is to boil it and collect the steam. You’ll need to have two bottles connected by plastic tubing. Heat the bottle holding the urine so it starts to boil. The steam will go along the tube and condense in the other bottle.
But it seems highly unlikely that you’d have all this stuff in a survival situation.
A better solution might be to make a solar still. It has to be very sunny for a solar still to work, and you still won’t get much water from it. But every drop counts in a survival situation!
What about Filtering Urine?
Outdoor water filters are usually rated to 0.2 microns. The Sawyer Mini water filter, for example, is rated for 0.1 microns. That means the filter will get out bacteria, parasites, and even some viruses.
However, we’ve already established that urine doesn’t have much bacteria in it. The issue is with the waste product compounds.
Many of these, such as urea and dissolved ions, are too small to be removed by a water filter. Other water purification methods like purification tablets and UV lights also do nothing to remove tiny compounds.
The best filter for urine is activated charcoal. It can actually remove a lot of the organic chemicals in urine. What activated charcoal won’t remove is inorganic chemicals like sodium – and it is the sodium which will really get you in a survival situation.
If you have a filter, it is still a good idea to filter the urine, just don’t expect it to be completely safe to drink afterwards.
Have you ever drank urine for survival? Tell us your stories!
“Puits Solaire” by Solar_still.svg. Licensed under CC BY-SA 3.0 via Commons
“Auto-Urine Therapy” (CC BY-NC-SA 2.0) by counterclockwise
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