There is no benefit for having 2 liters of water a day, it does not increase 'toxin excretion' or have any other supposed benefits[1]. Humans have evolved a great system to know when to drink, its called thirst! The old wives tail that "if you are thirsty you are already dehydrated" is just bunk.
Drinking excess amounts during food intake or prior to food intake is even worse, as I mentioned, it dilutes your stomach acid, leading to decreased nutrient absorption and increases chances for pathogens to pass through.
Drink when your thirsty, only enough to quench your thirst!
