The whole thing about drinking 8 glasses of water every day - it's a myth. You don't need that much water. If you do a quick search online, something like "myth that we're not drinking enough water" you'll find research on it.

I think the reason that this notion sticks around is because it's appealing. You can solve your health problems by something so simple...drinking water.

A friend of mine, very obese, had a huge jug of water that she lugged around all day, something like the attached image. She spent a lot of mental and physical energy (the number of bathroom trips! wow!) drinking the whole thing, daily. That energy would have been a LOT better spent on eliminating processed food.