Every living organism we know of requires to survive. It is part of the reason we look so feverishly for water on other planets across the universe and consume it consistently everyday here on earth. So what would happen to your body if you stopped drinking water?
Of course, when we say water we are including all fluids which simply contain water like juices, pop or tea. Much like the desire to breathe in oxygen, thirst is a survival instinct. H20 is the most abundant molecule in the human body making up on average 65% of an adult. As a universal solvent, it carries nutrients and hormones through the body, regulates body temperature, cushions our joints and even lubricates our eyes. You produce around 1.5 liters of urine everyday with another liter lost from breathing, sweating and pooping. Hence, to compensate the water loss, if we do not drink enough water, then we will get dehydrated.
So it is essential that the body replaces this liquid. The thirst center of the brain is located in the hypothalamus and is constantly using sensors in your blood vessels to monitor the amount of sodium and other substances in your body. For example, if you sweat too much, your blood volume and pressure fall. The brain then detects this change and creates the urge to drink something now. So what happens if you are unable to satisfy this thirst?
We need water for various purposes like digestion and excretion. Water is also a major component of blood. The initial signs of dehydration are the obvious dry mouth following which your urine becomes darker with a stronger odour as your body attempts to consume more fluids. The lack of H2O then begins to affect your brain. You might feel light-headed, have a slower response time and decreased ability to feel pain. In fact, when you’re dehydrated your brain tissue literally shrinks. It informs kidneys to retain moisture, thus producing darker, concentrated urine. It reduces the production causing dry mouth. We get headaches. Our energy levels drop and our skin becomes dry. Besides this, chronic dehydration can lead to severe health problems and even death.
In studies observing hydrated vs. dehydrated participants, the same task required more brain power and oxygen in dehydrated individuals compared to those fully hydrated. After a day or two with no fluids you’ll stop peeing altogether, have trouble swallowing, suffer from muscle spasms and likely experience nausea. After all, your body can survive without food much longer and attention to digestion is not a priority at this point. Eventually victims may become delirious with severely impaired brain function. Interestingly studies looking at elderly patients who suffer from delirium found that many are suffering from chronic dehydration in the first place. After even more time without water, the blood stops flowing to your skin, reducing heat loss but increasing your core body temperature. This can lead to a gray bluish tinge to your skin. Beyond three to five days without water, your body will begin to shut down its organs and eventually the brain.
But things that are considered healthy, beneficial or even essential can be considered just as dangerous in the wrong amounts. Yeah it turns out that those urban legends of folks dying from drinking too much water aren’t legends at all and death by water intoxication is a thing. So consider yourself warned. This condition is called as hyponatremia or “insufficient salt in the blood”. It basically means that you have diluted your blood too much. Chug 6 liters of water in a sitting and your kidneys probably won’t be able to flush it through fast enough. Your blood vessels swell up like water balloons. Some of your cells just can’t take up that much water. Death by dehydration and death by water intoxication have almost the same symptoms.
Of course, unlike the plentiful oxygen we breathe, only 2.5% of all the water is fresh most of which is locked up in glaciers, ice-caps, and underground lakes known as aquifers leaving less than 1% available for drinking and most of this water is actually used to grow crops. Approximately 500 billion liters of fresh water is used daily for agriculture in the USA alone with another 500 billion liters used to cool electric power plants. And as our personal drinking sources become increasingly contaminated, over 783 million people on earth are unable to access clean water.
Scientists from around the world are trying to find solutions to this problem from attempts to remove salt from the ocean water, tap into underground aquifers and creating innovative water filtration systems. But we can’t just rely on science and technology, perhaps the solution relies on us as a species to understand and contribute to this global water crisis.