Hiya there is a lot of evidence that shows that too much water in your body at one time can be very dangerous... you only have to google it...
The problem happens when we drink so much water, are kidneys have no time to extract nutrients passing through them and then they get flushed away with the water when we pee.
Drinking too much water without peeing is alos very dangerous!
We all have an amount we can drink that is right for us... If i go much about 3litres, I start to get dizzy and feel quite odd, others on here drink 5 litres a day.
CD advises 2.5 litres on top of water for shakes, (think this is right) you may be able to have more than this... just sip through the day, ensure you have your minimum amount and if you feel ok that you're having more, go for it...
x