If so much of our bodies are made of water, why do we still need to drink so much? Well, we lose a lot of water everyday from things like sweating and going to the bathroom, so we need to replenish that loss by drinking water.
In some cases you can even become over-hydrated from drinking too much water and suffer from water intoxication. So how do you know how much water is the right amount?
Watch the video above from TED-Ed to get all the details on water and how much our bodies need to be healthy.
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