Guide · body · 3 min read
Do you actually need eight glasses of water, without the usual advice, if you are sceptical about all of this
Eight glasses is a number with no particular evidence behind it. Thirst and urine colour are better guides.
Start here
None of this is glamorous. All of it is doable, which matters more.
Scepticism is welcome. You do not have to believe anything for this to work.
If you only do one thing from this page, do the first point below. It is first because it removes the most friction for the least effort.
What helps
There are real exceptions: hot weather, exercise, illness, pregnancy, and some medications. In those cases thirst lags behind need.
Your kidneys are extremely good at telling you what they need. Thirst is a reliable signal for healthy adults.
Drinking more than you need does not improve skin, concentration or health. It mostly increases trips to the toilet.
What to do when it does not work
Pale straw-coloured urine is the simplest check. Dark yellow means drink more; completely clear means you can stop.
Tea and coffee count. The idea that they dehydrate you is largely wrong at normal intakes.
Food supplies a meaningful share of your water, especially fruit and vegetables.
A note on effort
Stay with what you can actually feel.
Questions people ask
Does coffee dehydrate you?
At normal intakes, no. The diuretic effect is small and does not outweigh the fluid you are taking in.
Written for people who want the practical version. No accounts, no tracking, no newsletter wall.