Don’t force yourself to drink water just to hit “8 glasses a day”
Original: eternity4719 · source details
Original author: eternity4719 · Chinese source: · English adaptation: parveen0029. Translation and grade notes ↗
Bibliographic titles are retained in their original language.
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Cost and benefit at a glance
- Check the cost Cost ↓
- No cost at all. It does require some time and effort to remember to drink, and you’ll likely need to get up more often at night to pee.
- Then the source benefit Benefit ↓
- One literature review specifically examined the “8×8” rule — that is, 8 glasses a day, each glass holding 8 ounces of water. Its conclusion was that “no scientific research support…
In plain terms
Some people have tried to trace the origin of the “8 glasses a day” rule, but no studies supporting it have ever been found. On the contrary, surveys of thousands of adults’ diets and fluid intake show there’s no need for that much water at all, since food and other drinks already provide plenty. Just drink when you’re thirsty, and use the color of your urine as a guide — that’s all you need to do. People working in hot environments, those doing intense exercise, people who’ve had kidney stones, and older adults who no longer feel thirsty as readily should make a conscious effort to drink more water.
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Cost: what it takes
No cost at all. It does require some time and effort to remember to drink, and you’ll likely need to get up more often at night to pee.
Benefit: what the source reports
One literature review specifically examined the “8×8” rule — that is, 8 glasses a day, each glass holding 8 ounces of water. Its conclusion was that “no scientific research supporting the 8×8 guideline has been identified.” It also noted that “surveys of thousands of adults’ food and fluid intake strongly indicate there is no need for such a large volume of water intake,” since food and other drinks already supply plenty of moisture. This idea seems appealing because water costs nothing, the number 8 is easy to remember, and saying “drink more water” never seems like a bad piece of advice in any context.
Conditions, limits and disagreements
This recommendation refutes the idea that there’s a strict minimum number of glasses of water you must drink each day — it does not say that drinking more water is harmful. Just drink when you’re thirsty and check your urine color; that’s sufficient. People working in hot conditions, those doing heavy exercise, people with a history of kidney stones, and older adults who no longer feel thirst as keenly should make a point to drink more water, even though this guideline does not apply to them.
Original references
Original bibliographic titles and links are preserved; some titles are in Chinese.
Valtin H (2002). "Drink at least eight glasses of water a day." Really? Is there scientific evidence for "8 x 8"? Am J Physiol Regul Integr Comp Physiol. https://doi.org/10.1152/ajpregu.00365.2002
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