The world is heading towards a grave water crisis and the sources of freshwater are depleting at an exponential rate. You are lucky if you have access to clean water for drinking and other purposes. There are people who must ration their water usage intently and be actively mindful in consuming water even if it is for drinking. The question arises that our earth is around 70% percent water. So why can we not use it for drinking and put an end to the crisis we are facing? Let us dissect this concern.
Some people believe that it is likely we had the ability to digest seawater but with evolution, we lost it like other terrestrial mammals. If we investigate the biology of our bodies, our kidneys need to remove salt in the urine we produce to maintain the homeostasis of our bodies. The ocean water is saltier than our blood and if we drink it, the kidneys will have to get water from our internal sources like cells of other organs which will lead to hydration and death in a quite short span of time.
There are some species like albatrosses, sea lions, and gulls that have the systems in their bodies to process seawater and separate the excess salt from water. For example, albatrosses have a gland that takes in the salty water and excretes salt, keeping the water for the body.
Research has revealed that even the mammals inside the seawater do not rely entirely on the seawater for their water consumption. They extract it from the food they consume. More research needs to be done for clarity in their water consumption patterns. Some produce water from their biological processes and use it to quench their thirst.
However, humans can only acquire 20% of their water needs from the metabolic processes of their bodies. The rest must be compensated from the regular outside water sources. Hence, it is extremely necessary for humans to be responsible for consuming water and not waste it as it can lead to eventual death from thirst.