Age-old stories and advice would have us believe drinking a gallon of water a day will solve every problem, from weight loss to anti-aging. You can even trick your brain into drinking more water for those very reasons. But is it a myth?
Right at the top, let's clear up one aspect of the legend: Not everyone needs an entire gallon of water daily. "While striving to drink a gallon of water a day is great, there are different requirements of water intake depending on gender," says Margarita Lolis, MD, a board-certified dermatologist with Schweiger Dermatology Group. "Men often are the ones who require a gallon of water a day, and women are around 2.7 liters, according to the Mayo Clinic. A gallon of water is around 3.7 liters."
With that in mind, we asked Lolis and other fitness, nutrition, and skincare experts about what upping our water intake really means for our health and well-being. While guzzling water is not a cure-all for any and every body-related issue, there are seven major ways that added hydration will impact your life. Read on to find out what they are.
Your Metabolic Rate Might Spike
"Get this: If the human body consumes 16 ounces of water in a given hour, the metabolic rate will spike by as much as 30 percent for the next 30 to 40 minutes," says Heidi Powell, a celebrity trainer and fitness blogger. "By committing to drinking half your body weight in ounces of water each day, research says you can expect to lose more weight."
The cause? "There is a single enzyme—called lipase—that must be activated in your body in order to mobilize fat (i.e., get rid of it)," she explains. "Water is one of the many necessary components in [activating] lipase."
You'll Level Up Your Workouts
"In terms of fitness, water is the key to healthy, well-functioning cells," says Kara Griffin, a personal trainer, holistic nutritionist, and health coach. "So drinking enough is going to help with exercise on a cellular level." Studies have shown dehydration most negatively affects endurance exercise, so make sure you are hydrated during long runs. "Strength and power workouts (think CrossFit) are less affected by dehydration, but studies have shown some detriment to or lack in performance," says Griffin.
You Could Experience More Cramping
Though proper hydration will help you maximize workouts, it's important not to down your entire water bottle immediately before your sweat session. "Staying hydrated will increase performance across all exercise forms, but chugging water before a workout can cramp you up and make you feel more sluggish and less focused on the task at hand," says Griffin. "Drink a glass of water 20 to 30 minutes before your next workout, and take little sips throughout (if needed) to get you closer to your personal peak performance."
Boosted Energy Stores
Additionally, water helps your body maintain and regulate its energy stores. "You need water to bond to glycogen to create an energy reserve in your muscle (this is called ATP)," adds Drew Logan, a fitness expert and author. "Without water, you are less capable of storing energy because there is less oxygen in the muscle, less blood flow when you're dehydrated, and less delivery and bonding of glycogen to create the energy needed." In other words, drink up to power up.
Skin May Look More Radiant
"Dehydrated skin looks like crinkled tissue, often cracked and flaky," says Lolis. "People who are consistent with their water intake will likely have fewer wrinkles, less dryness, and less irritation to the skin."
Under-Eye Area Will Look More Refreshed
"Dark circles under the eyes could be a sign of dehydration in the skin," Lolis tells us. "Because the skin around the eyes is thinner, it becomes harder for capillaries to move fluids around if the area is not properly hydrated. By drinking more water, your cells will maintain steady hydration. Combine your increased water intake with a good under-eye cream, and you will look bright and more refreshed in no time."
"From personal experience... both eating high-sodium foods (particularly at night) and not drinking an adequate amount of water can definitely cause you to retain excess fluids around the eyes and experience more-than-normal under-eye puffiness," adds celebrity esthetician Reneé Rouleau. "I know firsthand that when I have not been drinking enough water during the day, the following morning, I will always be puffier under my eyes."
Dietary Habits Will Change
Drinking a gallon of water a day will also impact your eating habits. "First, drinking this much water will replace sugary drinks," says Griffin. "It's also important to remember that water intake doesn't just come from guzzling water—it also comes from what you eat. You naturally up your water intake by eating clean, unprocessed whole fruits and vegetables."
Drinking enough water and eating whole fruits and veggies also means you're eating fewer processed foods, which are usually high in sodium. "Salt stimulates the appetite [and] makes you retain water, causing you to eat more and bloat from the water you've been drinking throughout the day," says Griffin. "Without the salt, the water will help with intestinal motility and urination, two ways your body releases toxins." And don't worry about missing the junk food: Water "can help curb cravings since dehydration tricks your body into thinking it's hungry," Lolis tells us.
An easy of a snack that will help up your hydration? Watermelon, which is more than 93 percent water.
So yes, drinking water is incredibly good for you. But thinking drinking an entire gallon of water each day will solve every problem you have is a stretch. Make sure you're getting enough hydration, but also be mindful of the other elements required for good health—diet, exercise, and a smart skincare routine go a long way.
How much water do you need to stay healthy? Mayo Clinic.
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