The Science of Hydration: How to Optimize Your Water Intake for Better Health from Andrew Huberman

Water is essential for every function in the human body, making up 60-80% of human cells and tissues. Proper hydration plays a crucial role in maintaining cellular function, cognitive performance, and overall well-being. Even mild dehydration can negatively impact mood, focus, and physical performance, leading to brain fog and fatigue.

How to Optimize Hydration

To stay properly hydrated, aim to consume 80 ounces of water within the first 10 hours of waking, spread evenly throughout the day. The body’s circadian rhythm regulates kidney function, making early hydration more effective at maintaining fluid balance.

Tips to Reduce Nighttime Urination

• Hydrate sufficiently during the day.
• Limit fluid intake 2-3 hours before bed.
• Sip water slowly at night if needed, as rapid intake increases urination.

Hydration Needs During Exercise & Heat Exposure

Beyond daily hydration, factors like exercise, sweating, heat, and caffeine increase your water requirements. Use the Galpin Equation to determine additional hydration needs:

💧 Body weight (lbs) ÷ 30 = ounces to drink every 15-20 minutes 💧 Body weight (kg) × 2 = milliliters to drink every 15-20 minutes

Adjust for high heat or sweating by increasing intake by 50-100%. If using a sauna, drink an additional 8-16 oz of water for every 20-30 minutes spent inside.

⚡ Caffeine and Hydration: Since caffeine is a diuretic, increase your water intake by 2:1 (e.g., for an 8-ounce coffee, drink 16 oz of water). Adding electrolytes like sodium, potassium, and magnesium helps balance hydration.