Knowledge Base
Why the "8 Glasses a Day" rule is outdated
For decades, people were told to drink 8 glasses of water a day. However, modern science shows that hydration is highly personalized. A 50kg person sitting in an air-conditioned office needs significantly less water than a 90kg athlete running in the summer heat. This calculator uses your exact body weight and activity level to generate a custom target.
Does Coffee or Tea count towards my water intake?
Yes! While caffeine is a mild diuretic, the water content in a cup of coffee or tea easily offsets the dehydrating effect. However, pure water remains the healthiest and most efficient way to hydrate your body without added calories or sugar.
Signs you might be dehydrated:
- Dark urine: Your urine should be pale yellow or clear. Dark yellow is the #1 sign of dehydration.
- Brain fog & Fatigue: Even a 2% drop in hydration can cause significant cognitive decline and sleepiness.
- Dry skin and lips: Water is essential for maintaining skin elasticity.
- Headaches: Dehydration can temporarily shrink the brain, pulling it away from the skull and causing pain.