Effects of water intake on the fluid balance of the body?
As your body becomes saturated your cells swell up with the
water. If you are slightly or severely dehydrated, your cells
shrink, but when you drink water they "plump" back up to a healthy
size and are able to exchange gases (like oxygen and carbon
dioxide), amino acids (proteins in your food and in your body), and
hormones productively again. This is one reason why people feel
tired when slightly dehydrated and a simple glass of water can perk
them up.
But if interested, one can actually overhydrate their body and
drown from the inside out because cells will burst when
oversaturated and it is possible to burst too many. Most people do
not need to worry about this at all, though, because most people do
not drink enough water and are slightly dehydrated much of the
time.