hey there!  welcome to the new episode of Curiosity! A series in which we will answer some of the questions that makes us all curious. 

Imagine you are stuck in a desert,what would you do to survive. Well, firstly you would look for a nearby source of fresh water, but you aren't able to find one. Next thing you would do is wait patiently for a rain to occur but the sky above you is perfectly clear. Also you are not able to find any plant from which you can extract water from or you simply have no idea that how to extract water from the plants. You are dehydrating more and more as the time passes. Losing all your hope , you have only one option left, drinking your own urine. Well, it seems like a logical option, after all we have seen in movies and heard from different survivors , that drinking their own urine kept them hydrated. In fact, Aron Ralston  who amputated his own arm to escape Utah canyon have similar opinion.but can drinking your own urine can save your life in a desert ? Lets find out.

What's Urine and it's Composition?

Urine is the by-product in the form of liquid secreted by the kidneys. This waste product is secreted by the renal tubules of the kidneys, which then accumulates in the urinary bladder and excreted through urethra by the process of urination. The normal Urine mainly consists of 95% water, but also includes nitrogenous components like urea , creatinine and many other waste products. Infection may cause other unwanted substances to be extracted from the urine. Let's look at the various properties of urine.

Fig: Urine (Credits)

Physical Properties of Urine

The normal pH of urine ranges from 5.5 t0 7 which is slightly acidic in nature. The urine excretes about 100kcal/day. The high protein diet leads to the more acidic urine , but vegetables leads to more alkaline urine. The colour of urine is generally, yellowish-amber but it depends on the recent diet and the water intake. The darker urine indicates Dehydration.

Composition of Urine

Fig: Composition of Urine (Credits)

The Excreted urine is Mostly 95% water and rest of the 5% solute only consists of only 68 types of solutes which might be organic and inorganic substances. These solutes have the concentration of 10 mg/L and can be classified as the Nitrogenous wastes such as Urea and creatinine , similarly various Vitamins and Hormones also various types of electrolytes such as sodium potassium and chloride ions. So, the overall normal organic urine composition is:

• Urea. 
• Creatinine.
• Uric Acid.
• Others. 

The Overall Normal Inorganic composition of Urine is:

• Sodium (Na) : 3-5 g/Day
• Potassium(K): 2.-3 g/day
• Chlorides: 10-15 g/day
• Calcium : 0.1-0.4 g/day
• Ammonia : 0.8-1 g/day

so, Can you Survive by Drinking your Own Urine?

As, Explained above, A normal Urine is approximately 95% water and sterile. But rest of the 5% is just the massive collection of waste products which if taken in too much amount can surely cause some serious problems. After all, urine is just the body's way of removing the waste products. The more dehydrated you become, the more of these solutes will be excreted via urine making the urine more and more concentrated.

When you are stuck in a desert, you are likely already mostly dehydrated. Which produces more and more concentrated urine. At this most Desperate time, you are searching for water, and losing all hope you decide to drink your own urine.

Well, this might not help you at all. After drinking your own urine , you are taking in all the garbage back, that your body threw away. This can raise the toxicity in the body. 

In short term, Yeah, It's safe and does manage to bring back some of the lost water but in long term or may be after several hours, your urine will be highly concentrated in nature and is packed with very toxic waste products. In turn your Kidney needs to work harder in oder to produce more urine. This might lead to a Kidney Failure. 

Fig: Osmosis (credits)

But the main reason is, the more concentrated urine , draws out more water from the body into the intestine by the principle of osmosis. The principle of Osmosis states that, the molecules always tends to move from region of lower concentration to higher concentration. Since there is Urine is more concentrated than your blood, the water tends to move from body to the intestine. This speeds up the Dehydration process further more. 

Conclusion

Its safe , if the person is fully hydrated and might work for some days, but after few days drinking your own urine in this type of emergency situation can also cause vomiting and diarrhoea, which might speed up the dehydration process. Further more, drinking own urine acts like drinking the sea water, the more you drink, the faster it dehydrates you. So, this might keep you alive in the deserts and you might have to look for better options.

That's it for this Episode guys. Hope you Enjoyed it. If you did Up-vote and comment your thoughts below. Thank you

Stay Curious. 

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References Used:

[1]- The yellow Diet

[2]- Is it safe to drink own Urine

[3]- Urban Survival Myths 

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