How it works
Tap the container you drank from and the jug fills by that amount. Make your own containers ("My bottle, 750 ml") with Other; the ones you use most move to the front. Each drink is its own band in the jug, so you can see the day's refills, and the jug empties when your day starts again.
The goal is yours to set. For context, the National Academies (2004) found that healthy women typically take in about 2.7 liters of water a day and men about 3.7 liters, counting the water in food; drinks supplied about 2.2 and 3.0 liters. Those are typical intakes, not targets: the panel set no glasses-a-day rule, and found that thirst and drinks with meals keep most people hydrated. Heat and hard exercise raise needs.
The familiar "8 glasses a day" has no study behind it: a 2002 review looked for one and found none. Coffee and tea count.
Everything you log stays on this device.
Questions people ask
- How much water should I drink a day?
- There's no single number. The National Academies found healthy women typically take in about 2.7 liters of water a day and men about 3.7, counting food, with about 80% from drinks (around 2.2 and 3.0 liters). They set no glasses-a-day rule and say thirst and drinks with meals cover most people; heat and exercise raise needs.
- Is "8 glasses a day" true?
- It isn't based on evidence. A 2002 review in the American Journal of Physiology searched for the origin of "8 x 8" and found no scientific studies supporting it, for healthy adults in a temperate climate. The NHS suggests 6 to 8 cups or glasses of fluid a day as a guide.
- Do coffee and tea count?
- Yes. The National Academies concluded that caffeinated drinks count toward daily water intake as much as other drinks.
- Does food count toward water intake?
- Yes. In US survey data about a fifth of total water came from food, which is why the National Academies give a total figure and a smaller one for drinks.
- Can you drink too much water?
- It's possible: the National Academies note that healthy kidneys can get rid of about 0.7 liters an hour at most. This tracker doesn't judge amounts; if you're unsure what's right for you, ask a doctor.
Sources
- National Academies: report sets dietary intake levels for water, salt and potassium (February 11, 2004)
- Institute of Medicine 2005: Dietary Reference Intakes for Water, Potassium, Sodium, Chloride, and Sulfate, Summary (Table S-2)
- Valtin 2002: 'Drink at least eight glasses of water a day.' Really?
- NHS: water, drinks and your health
- NIST SP 811, Appendix B: conversion factors (fluid ounce)