What Happens When You Drink a Gallon of Water a Day?

I am that person who hates drinking water. Most days, I avoid doing so entirely, subsisting on coffee, herbal tea, and the occasional LaCroix. But a few months ago, I began to suspect that chronic dehydration was the reason I continually felt tired and achy. So, to adopt better life habits, I decided to take on a feat known across the internet as the Water Gallon Challenge: drinking a gallon of water per day for a month, with the promise of glowing skin and a lot more energy.

Given my taste sensitivities, I went the filtered route. I brought with me a hoard of limes, cucumbers, and sea salt, plus an emergency stash of electrolyte mix and a journal to track my energy, yoga performance, and bathroom breaks. Here’s how it went.

I Drank a Gallon of Water a Day. Here Are My Journal Entries.

I was diligent in my notetaking during this challenge; these are the highlights:

• Day 1: I’m peeing every 15 minutes. How in the hell am I supposed to get anything done?
• Day 2: I did not think it was physically possible to pee more than I did yesterday (21 times), yet here we are, 23 times. Additional instances of bodily rebellion include an afternoon of mild nausea and a slight headache.
• Day 4: I didn’t feel like a 70-year-old woman when I got out of bed this morning. I deep-cleaned my house with the stamina of an old-school Disney princess. Is water the magical cure for the generalized fatigue my doctor insists is not a real thing?
• Day 5: Yes! Water is life! I no longer hobble into my day with my feet and spine curled up like dry leaves. I thought this experiment would be miserable, but I totally get it now. (Though to be clear, water—even filtered water—still tastes disgusting without flavor enhancements.)
• Day 7: Can we talk about how good I am at yoga right now? My hamstrings are much more flexible, and I can back bend with ease. Even better, I have energy afterward, and I’m not horribly sore the next day.
• Day 10: A switch to water that’s been ultrapurified by reverse osmosis (plus “carbon polishing” and UV sterilization) has proved revelatory. It’s fully palatable and delicately sweet, without a hint of chlorine. I’m now the proud owner of a refillable three-gallon jug.
• Day 14: I crave water instead of coffee first thing in the morning. I don’t recognize myself anymore.
• Day 19: The peeing has decreased to ten times per day. I’m still acutely aware of how much water I’m flushing down the toilet, so I’ve donated $30 to Charity: Water, which funds clean-water projects in 26 countries.
• Day 24: My massage therapist confirms that my muscles and fascia are noticeably looser. She’s shocked to learn that before this, in the two-plus years she’s been trying to fix my body, I had been drinking barely any water.
• Day 32: Oops, the month is over, and I didn’t even notice—hydration is routine, and I’m loving it. Am I going to keep guzzling 128 ounces every day? Not unless I’m sweating buckets. But you better believe I’ll keep sipping on glorious, ultrapurified water like my well-being depends on it.

How to Stay Hydrated, According to a Nutritionist

Nicole Lund, a nutritionist at New York University’s Langone Sports Performance Center, explains the basics of hydration and how much water you should be drinking each day.

“Proper hydration means 85 ounces of water a day from food and beverages, plus more to replenish what you lose when exercising.” (That’s roughly four ounces of water for every quarter-pound of weight lost during your workout.)

“Physiological changes occur even in the early stages of dehydration, including decreased blood volume and less oxygen delivered to working tissues. These changes make it harder to sweat, which will increase body temperature and heart rate and make you feel more fatigued during exercise.”

Keep in mind that frequent trips to the restroom are normal with increased water intake, and it will take some time for your body to adjust, Lund says. As a reminder: “We all wake up slightly dehydrated. The easiest change you can make is to have a big glass of water first thing in the morning.”

Have questions about Aleta’s Gallon Challenge? She answered some FAQs here.

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