With temperatures reaching 100 degrees in Altadena, I’m sharing these hydration tips from Dr. Andrew Huberman’s Podcast. YouTube link to the full episode.
Water is a vital nutrient, making up approximately 60-80% of human cells and tissues.
Dehydration (even mild dehydration) negatively impacts physical performance, alertness and cognitive focus, and thereby can cause “brain fog.” To ensure proper hydration, consume 8 oz (237 mL) of fluid per hour for the first 10 hours of your day. Note: these are averages! You do not need to consume 8 oz every hour neurotically but rather 16 oz on waking, then 8 oz a few hours later, 32 oz later, 4 oz, etc. Eighty ounces in the first 10 hours of your day, spread out as practical, is fine. The issue is simply that most people do not drink enough water during the waking hours of their day. Drinking ~80 oz in the first 10 hours after waking can help most people offset dehydration.
Exercise, Heat and Hydration
Above meeting your baseline hydration requirements (80 oz/10 hrs of waking), other factors such as exercise, sweating, excess heat, dry environments, and caffeine intake affect your hydration requirements. When exercising, follow the Galpin Equation as a guideline for the amount of additional fluid you should consume (again, on average — no need to be neurotically obsessed with consuming exact amounts at exact times during exercise unless you prefer to.
The Galpin Equation:
Body weight (in lbs.) divided by 30 = number of ounces to consume every 15-20 minutes
Body weight (in kg.) × 2 = number of mL to consume every 15-20 minutes
If you are in hot temperatures or sweating, increase the Galpin Equation guidelines by an additional 50-100%. For every 20-30 minutes in the sauna, consume an extra 8-16 oz of fluid.
Also, be mindful of how caffeine consumption increases your overall water intake needs, as it is a diuretic. If you drink caffeine, increase fluid intake (ideally with electrolytes like sodium, potassium and magnesium) by 2:1 to offset dehydration. In other words, if you drink an 8-ounce coffee with caffeine, ingest 16 oz of water, ideally with low/no-sugar electrolytes like LMNT, or simply a pinch of salt.
Thirst indicates that you are not sufficiently hydrated, but your perception of thirst lags behind the body’s true hydration status. So not being thirsty does not mean you don’t need more fluid. Therefore, preemptively plan your hydration strategy, especially in extreme weather or high-intensity activities.