[lapama]

Rule of thumb: if expulsed urine volume (after fall) exceeds ripe lemon color, you have to drink more. How this relates to the paper? Only intuitively.

[Tepix]

Here's something to aim for: Drink enough so that at least once per day your urine is clear.

[hooli_gan]

As a child my rule was: Pee should look like Sprite, not Fanta.