Does Drinking a Gallon of Water a Day Have Benefits? Here’s What Experts Say

Stay hydrated, folks

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By now, we’re all pretty familiar with the importance of staying hydrated throughout the day. But what does “staying hydrated” even mean? Many folks opt to aim for the nice, square number of 1 gallon of water a day (for reference, 2.7 liters equal about 0.7 gallons), so we looked into the health benefits of drinking that much H20, from speeding up metabolism to preventing headaches.

Firstly, Do We Need to Drink a Gallon of Water a Day?

The short answer is, not necessarily. Although there’s no consensus on how much water people should drink each day, the Centers for Disease Control and Prevention (CDC) and the Food and Nutrition Board (FNB) say each person’s guide should be their own thirst. If you’re feeling parched, drink some water—simple as that. As a very general guideline, the FNB suggests women should drink around 0.71 gallons of water daily and men around 0.98 gallons.

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5 Health Benefits of Drinking a Gallon of Water a Day

1. It Might Improve Your Metabolism

Anyone who’s ever tried to drop a few pounds knows that, alongside a healthy diet and consistent exercise, hydration is key. Drinking water (approximately 16 ounces) can increase your metabolic rate by 30 percent, according to a 2003 study in the Journal of Clinical Endocrinology and Metabolism.

2. It Might Prevent Headaches

Dehydration is one of the leading causes of that throbbing pain in your skull. Think of a constant stream of water as a measure that helps prevent a headache from developing. (Just be sure you keep sipping throughout the day.)

3. It Can Help Your Kidney Flush Toxins from Your Body

Water helps the kidneys remove wastes from your blood in the form of urine, per the National Kidney Foundation, which notes, "Water also helps keep your blood vessels open so that blood can travel freely to your kidneys, and deliver essential nutrients to them. But if you become dehydrated, then it is more difficult for this delivery system to work."

4. It Helps Clear Brain Fog

According to a 2019 study published in the International Journal of Environmental Research and Public Health, research shows that dehydration has “negative effects on vigor, esteem-related affect, short-term memory and attention” and, “rehydration after water supplementation improved fatigue, TMD, short-term memory, attention and reaction.” Makes sense, considering water makes up 73 percent of the brain.

5. It Helps Keep You Regular

According to the National Council on Aging, water is necessary to keeps things flowing through your gastrointestinal tract to prevent constipation. Why? "It aids in breaking down soluble fiber from your diet to keep your digestion process on track."

Do You Need to Drink a Gallon of Water a Day?

Hydration is crucial, but a gallon is, for most folks, a little more than necessary to stay hydrated. While drinking more water than your body technically requires shouldn’t be bad, a 2010 Dutch study found that drinking more than your body’s required amount of water didn’t have any more benefits than drinking just enough. You should drink when you’re thirsty, and if that means drinking a gallon a day, great. If it means a little less, that’s also great. If you’re not sure how much water you should be drinking, consult your doctor.

Can Drinking a Gallon of Water a Day Be Harmful?

According to the experts at Cleveland Clinic, drinking a gallon of water a day isn't harmful—with a few exceptions. "[For] those who have congestive heart failure or end stage kidney disease, sometimes water needs to be restricted because the body can’t process it correctly." If you or anyone in your care falls into one of those groups, talk to your doctor about how much water you should (or shouldn't) be drinking.

Also be aware of water intoxication, a disruption of brain function, per researchers at the Cleveland Clinic, caused by drinking too much water.

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5 Things That Might Happen if You Drink a Gallon of Water a Day

1. You’ll Have to Pee All the Time

This one isn't too shocking: Drinking more water will mean more frequent urination. You’ll also be doing that other bathroom business regularly, now that your body is breaking down its food more easily. And the last bonus? Those frequent bathroom breaks ensure that you’re moving around more throughout the day.

2. You Might Eat Less

OK, so this one might depend on your age. A 2010 study by researchers at the Department of Human Nutrition, Foods and Exercise at Virginia Polytechnic Institute and State University found that, for middle-age and older adults, drinking water before each meal could decrease appetite, while a second study published in 2008 showed that it increased weight loss by 4.4 pounds over a 12-week period.

3. You Might Have Better Workouts

Per a 2013 paper published in the American College of Sports Medicine's Health & Fitness Journal, "Water acts as a transporter of nutrients, regulates body temperature, lubricates joints and internal organs, provides structure to cells and tissues and can help preserve cardiovascular function." Make sure to drink frequently two hours before your workout, every 20 minutes during and directly afterward to keep your body properly hydrated.

4. You Might Lose Weight

"Studies of individuals dieting for weight loss or maintenance suggest a weight-reducing effect of increased water consumption," according to a review in the Journal of American Clinical Nutrition. Think about it: You’re peeing away the extra bloat, you’re eliminating waste regularly, you’re eating less and you’re working out more efficiently. While drinking more water in itself won’t make you lose weight, the positive side effects just might.

5. You’ll Find Yourself Craving More Water

The more you drink it, the more you’ll want it. Luckily, the stuff is free, pure and as evidenced above, the absolute best for you.

7 Tips for Drinking More Water

1. Make It Part of Your Morning Routine

Having a glass of water as soon as you wake up is great for a host of reasons, but it also sets you up for a day of top-notch hydration. Before, or—fine—while you make your first cup of coffee or tea, have a glass or bottle on hand to start the day off right.

2. Set a Specific Goal

Studies have shown that being deliberate about what you want to accomplish makes you way more likely to actually accomplish it. Instead of saying, “I’m going to drink more water,” think about how much you’re currently drinking and come up with an exact number of ounces (or bottles) that you’d like to get to.

3. Buy a Pretty Water Bottle

Superficial? Yes. Effective? You bet. Buy a bottle you’re happy to drink from and you’ll use it more often—simple as that.

4. Eat Water-Filled Foods

Cucumbers, grapefruit and watermelon aren’t only delicious snacks—they can also help keep you hydrated throughout the day. We’re not saying you should count solely on food for hydration, but it’s a great way to sneak some extra water into your system.

5. Use an App to Track Your Progress

We use apps for almost everything, so why should staying hydrated be an exception? Apps like Waterlogged (for iPhones) and Hydro Coach (for Android) make it easy to stay on track with your water-drinking goals.

6. Set an Alarm on Your Phone

At first, your coworkers might be annoyed by the alarm that goes off on your phone every hour on the hour signaling it’s time to hydrate. Before long, though, your body will get used to the schedule and you’ll be able to ditch the blaring reminder altogether.

7. Make Water More Enticing

Some people genuinely like drinking water. Others, not so much. If you’re in the latter camp, try spicing your bottle up with natural flavors from fresh fruits, veggies and herbs. Lemon-and-basil water, anyone?

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