Here's how much water you should drink every day

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We're guessing you've gotten the memo that water is très important for all healthy life function, no? And while we've all heard the daily recommendation to chug eight eight-ounce glasses of H20 every day, ever had a niggling curiosity about the accuracy of that that stat? And where exactly did the one about sipping water for clearer, glow-y skin come from? (We've even reported on a number of variations on that claim.) Here, we investigate the vague world of recommended water consumption — for your skin and your body — because it's about time we figure out how much water we should be drinking for optimal health, once and for all.

For Your Skin.
When it comes to daily water intake, here's a good rule of thumb to follow: Just keep sipping, for your complexion, anyway. "Keep drinking fluids throughout the day," says Elizabeth Tanzi, founder and director of Capital Laser & Skin Care and associate clinical professor, department of dermatology at the George Washington University Medical Center. "If you ever get to the point of feeling really thirsty, that's an indication of dehydration."

And it turns out, there's no right (or wrong) number of water glasses you should be sipping for a glow-y complexion, says Tanzi. "This is one of the biggest myths in all of dermatology," Tanzi tells Allure."Drinking six to eight glasses of water does not hydrate the skin from within. Drinking water is essential for overall health, but it has very little to do with the level of skin hydration." This is not to say drinking water can't make you look and feel better. It is to say that water contributes to a more holistic state of physical well-being — but it won't give you a Huda highlight at first sip.

But that doesn't mean you should forgo your daily aqua intake completely, says New York City-based dermatologist Joshua Zeichner. "There is no data showing that drinking fewer than eight glasses of water is harmful to the skin," he says. "The only caveat is that in cases of severe dehydration, circulation is directed away from the skin to make sure that your heart can function optimally. In this case, the skin may pay the price." When skin is dehydrated, which can happen in people who adhere to the eight eight-ounce glasses recommendation, says Zeichner, the skin becomes dry, flaked, and in some cases, wrinkled.

Your best bet for radiant skin? Incorporating hydrating skin-care products into your daily routine, says Tanzi. "The best defense is a good moisturizer that contains hyaluronic acid," she recommends. (Quick refresher: Hyaluronic acid is a sugar molecule found naturally in the skin, which increases skin's moisture content and prevents water loss. It can hold 1,000 times (yes, 1000!) its weight in water and is typically found in creams and serums, like the Best of Beauty-winning Neutrogena Hydro Boost Water Gel.) "This ingredient pulls water in to keep the skin well hydrated."

Bottom line: Drink water to be healthy, but don't expect perfect skin because of it. "It's true that the skin needs water, just like every part of your body to function properly," says Tanzi. "But as long as you drink enough fluids to maintain body hydration, you're fine."

For Your Body.
So, how much should we really be drinking? Good question. And one there isn't an agreed upon answer within the medical community, either. Even the Centers for Disease Control and Prevention, which says daily water intake "varies by age and sex," doesn't dole out specific numbers. Instead, it refers to a release by the National Academies of Sciences Engineering Medicine's Health and Medical Division that, again, doesn't specify exact requirements but sets general consumption recommendations — 91 ounces for women and 125 for men. If we're talking in eight-ounce glasses, that's more than eleven for women and nearly 16 for men.

Willow Jarosh and Stephanie Clarke, registered dietitians and co-founders of C&J Nutrition in New York City, seem to be on the same page. "Aim to start with the classic eight eight-ounce glasses a day and adjust for your personal needs," says the duo. "Every system and organ in your body works better when you're hydrated. This includes your detoxifying organs, like your liver and kidneys, which help rid your body of waste. Every cell in your body depends on water to function at peak."

It's true — even down to your appetite. In a 2016 study, researchers from the Wageningen University in the Netherlands found that drinking more water alters the satiety cues the stomach sends the brain. Which basically means that water can actually help trick your brain into thinking you're fuller — faster.

Another example of water doing your body good? According to a study by the University of Illinois at Urbana-Champaign, participants who increased their consumption of plain water by one percent (!) reduced their total daily calorie intake. What's more, researchers discovered that participants' consumption of saturated fat, sugar, sodium, and cholesterol had also decreased — just by drinking water.

Remember, your body needs water and a good way to tell if you're getting enough of it is to check the toilet after you pee, says Jarosh. "We always recommend that our clients use their urine as an indicator of hydration," she says. "To indicate hydration, they should aim for a pale lemonade color."