Hydration
Bodyweight in lbs ÷ 2 = oz/day.
Priority Matrix
The numbers.
Four dimensions, scored 1–6, where six is always the good end: cheapest, quickest, easiest, highest impact. Priority is Impact squared, divided by what it costs you in energy, money and time.
How sure we are
Kept separate from the priority score on purpose: confidence in the evidence never raises how worth-it something is.
What we read
- "Drink at least eight glasses of water a day." Really? Is there scientific evidence for "8 × 8"?
American Journal of Physiology — Regulatory, Integrative and Comparative Physiology · 2002
A literature search found no scientific evidence for the 8×8 rule — thirst and water in food already cover most people, and the kidneys simply excrete the surplus.
- Water, hydration, and health
Nutrition Reviews · 2010
Mild dehydration of about 1–2% of body mass is associated with worse mood, alertness, and physical performance, while daily needs vary widely with climate, size, and activity — not a single ounce-per-pound formula.
Research from Dartmouth Medical School · University of North Carolina. We cite their published work. They have no involvement with Anew.
Where this falls down
Still unknown. The bodyweight-in-pounds ÷ 2 rule on this card is a mnemonic, not a trial-tested dose; nobody has shown that hitting that number outperforms drinking to thirst for healthy adults.
Topics
Where it fits.
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