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You really don't need to drink eight glasses of water each day

You really don't need to drink eight glasses of water each day

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So you’ve probably heard that you’re supposed to drink eight, 8-ounce glasses of water every day, right? Well, turns out, that’s bullshit. Seriously, watch the video — someone lied to you.

First of all, there isn’t a set amount of water all humans need to drink. Each person’s water needs differ, depending on their health, size, diet, general sweatiness, and a collection of other variables that don’t tidily add up to eight glasses of water per day. There are also plenty of places to get water besides hitting the stuff straight-up. Alcohol and caffeinated beverages do contribute to your daily water intake. (Don’t believe me? Ask the Mayo Clinic.) In fact, you don’t even need to drink all your water — you eat about 20 percent of it with your food.

Even if the eight-by-eight “rule” were supported by science — and it isn’t — most people don’t need to actively track their water intake to stay hydrated. “The vast majority of healthy people adequately meet their daily hydration needs by letting thirst be their guide,” reports the National Academy of Sciences. Basically, if you’re thirsty, your mouth is dry, or your pee is weirdly dark, drink up. You don’t have to count glasses, because your body is keeping track for you.