How do we know that we need to drink?

While many people tend to think that the brain is the main ‘decider’ for our bodies, it turns out that it's not always true!
 
One of the coolest examples involved our kidneys! When our bodies sense that we need more water, our kidneys kick into action. They create and release a special molecule called “vasopressin”. Vasopressin travels along the bloodstream until it reaches the brain and the kidneys. 
 
In our kidneys, vasopressin works by increasing the number of water channels (called “aquaporins”). This allows water to flow back into our bodies helping us to stay hydrated. 
 
BUT vasopressin also tells the brain that we need to drink water! Interestingly, this is a sensation that we aren’t even aware of.
 
So, whenever you feel the urge to have a glass of water, you can rest assured that your kidneys are working hard behind the scenes. They help you ‘know’ that you need to have a drink!