HOW MUCH WATER DO I NEED TO DRINK?

We’re a hydration-obsessed culture. From fruit-infused carbonated drinks to coconut milk kefirs and reverse osmosis water, what we sip is a hot trend. If you’ve ever worked with a personal trainer, their first question to you was likely “How much water are you drinking?” It’s for good reason—the human body is composed of about 66% water, which is contained in every structure from organs down to our very cells. Hydration affects our mood, cognition, physical performance, and waste removal, just to name a few things—so how much water do we need to drink, anyway?

WATER INTAKE RECOMMENDATIONS

It’s not as simple a question as you’d think. There’s no official governmental guideline for water consumption, which is likely because the amount changes based on gender, body weight, physical activity, health, and climate. However, we can figure out a range based on upper and lower limits.

An article from the Mayo Clinic states the CDC recommends drinking a half-gallon of water per day in the event of a natural disaster (so you know how much to squirrel away in case of emergency.) This is in line with the old adage to drink eight 8 ounce glasses per day, though this recommendation appears to have no scientific basis.

Then there’s the upper limit. This is the amount of consumption that can lead to dilutional hyponatremia, which develops when the intake of water exceeds the kidney’s ability to eliminate it. Most cases of hyponatremia occur in endurance athletes who mistakenly overestimate how much they need to hydrate to compensate for activity. Studies suggest the kidneys can remove 20-28 liters of water per day, but not more than .8 to 1 liter per hour (about 33 ounces max.) Drinking more than this could be harmful.

THE SWEET SPOT

A 2004 study from the U.S. National Academies of Sciences, Engineering, and Medicine recommended 3.7 liters (122 ounces) per day for men and 2.7 liters (89 ounces) per day for women for healthy adults living in a temperate climate. As noted above, you may need more water depending on your size, activity level, and climate, as well as if you’re sick, pregnant, or breastfeeding. So how do you know how much more? Two factors are safe to use as guidance. Firstly, your thirst! Use thirst levels as a first indicator that you need hydration. Secondly, monitor your urine. Pale, watery yellow is a healthy color. If you’re not sure what this looks like, check out this handy urine color chart.

GO AHEAD, COUNT YOUR COLD BREW

Another key to remember is that water intake doesn’t come only from drinking plain water. High water content foods count as part of your intake (think fresh fruits and vegetables). Even meat has some water content! Additionally, while plain water is a great choice because it’s sugar and calorie-free, other liquids do contribute to your hydration—including caffeinated coffee and tea! Numerous studies show that for most, these beverages have only a mild diuretic effect—not enough to keep them from adding to your totals.

HOW TO KEEP TABS

We like to keep tabs on how much plain old flat water we’re drinking. Keeping in mind that fresh foods and other beverages count, we aim for around 80 ounces on active days. To follow suit, simply look at how many ounces your favorite bottle holds, and note how many full bottles you need to drink each day. It’s likely 3 or 4 if you’ve got a “normal” sized bottle. Make it a habit to take it with you everywhere! If you’re not into that water bottle life, note how many ounces your usual glass holds and make those calculations instead.