Be careful doing that. It takes a fair bit of water, but Water Intoxication is a real thing. It can make you quite ill and even be fatal.

Drinking too much water dilutes your blood and decreases the electrolytes in your body, especially sodium (hyponatremia). As a result, water moves into your body’s cells and causes them to swell. When you get too much water in your brain cells, it increases pressure on your brain and affects how it works. This leads to changes in your awareness, movement and behavior (altered mental status). Water intoxication is also potentially fatal.

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The amount of water that causes overhydration varies. It’s important to understand how your body uses water to know how much is too much for you. Your body removes excess water through your pee. In a day, this equals about 32 to 64 ounces (about 1 to 2 liters). In some people, water intoxication symptoms can develop after drinking about a gallon (3 to 4 liters) of water over an hour or two.