"Drink at least eight glasses of water a day." Really? Is there scientific evidence for "8 x 8"?

@article{Valtin2002DrinkAL,
  title={"Drink at least eight glasses of water a day." Really? Is there scientific evidence for "8 x 8"?},
  author={Heinz Valtin},
  journal={American journal of physiology. Regulatory, integrative and comparative physiology},
  year={2002},
  volume={283 5},
  pages={
          R993-1004
        }
}
  • H. Valtin
  • Published 1 November 2002
  • Medicine
  • American journal of physiology. Regulatory, integrative and comparative physiology
Despite the seemingly ubiquitous admonition to "drink at least eight 8-oz glasses of water a day" (with an accompanying reminder that beverages containing caffeine and alcohol do not count), rigorous proof for this counsel appears to be lacking. This review sought to find the origin of this advice (called "8 x 8" for short) and to examine the scientific evidence, if any, that might support it. The search included not only electronic modes but also a cursory examination of the older literature… 

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