All that my wife drinks (95% of the time) is water. She drinks it with no ice in a 32 ounce cup, so she is truly drinking a quart at a time, and she is most likely over 1 gal per day with no diuretic liquids.

Food for thought if I may.

My point is that the overall recommendation of 1/2 gal per day is way low for many people (if not most) in reality. And it is different to food. Yeah, we say 2000 calories/day and we actually eat 3200 or whatever, but this is vital to life. And an abrupt change in liquid intake might cause some sort of problem (physical or mental) to start.

Thank god I quit smoking last year.