That famous eight-glasses rule? It actually might trace back to a 1945 recommendation that said we need about 2.5 liters daily. The catch? That advice added that most of this water comes from food, not just your trusty S’well bottle. We conveniently forgot that second part, and boom—hydration dogma was born.
Your coworker who chugs a gallon a day isn’t necessarily wrong, but they’re not a universal model either. Age, climate, activity level, and even how much you sweat during a hot yoga class all change your personal equation. Think of your body as a custom sports car, not a stock sedan; you wouldn’t use the same fuel gauge for both.
