Hydration and Wellness: How Much Water Do You Actually Need?
Beyond the '8 glasses' rule — practical hydration guidance, including electrolytes and how to make water more interesting.
Hydration affects mood, focus, blood pressure, digestion, and skin. But the famous '8 glasses a day' rule has no real scientific basis — your real need depends on body size, activity, climate, and diet.
A reasonable target
For most adults: about 30–35 mL per kg of body weight per day, including food sources. A 70 kg adult lands at ~2.5 L total.
Eat your water
Cucumber, watermelon, citrus, soup, and yogurt are all 80–95% water and bring electrolytes.
Add a little salt
A pinch of sea salt and a squeeze of lemon in your first glass each morning supports the adrenal response and electrolyte balance.
Coffee and tea count
Their diuretic effect is modest. Caffeinated beverages contribute net positively to daily hydration.
Signs you're under-hydrated
Headache, low energy, dry lips, dark yellow urine, dizziness on standing.
Frequently asked questions
+Can I drink too much water?
Yes — rare but possible (hyponatremia). Match intake to thirst, climate, and activity. Don't force liters.
Sources & references
- The Nutrition Source — Harvard T.H. Chan School of Public Health
