Is There Such A Thing As Drinking Too Much Water?

Photographed by Andi Elloway.
If there’s one health and beauty adage you’ve probably heard on rotation throughout your life, it’s: Drink more water. Feeling dehydrated? Drink more water. Have a headache? Drink more water. Skin looking dull? Drink more water. Constipated? Drink more water. The latest trend: Drink more water…. by guzzling it out of a giant water bottle.
This year, oversized gallon water bottles became as popular as a Telfar drop, with celebs from Kendall Jenner and Dakota Johnson spotted schlepping their massive sherbet-coloured bottles around Los Angeles. These aren’t your everyday Nalgenes and Swells. These bottles are decked out with hour indicators alongside encouraging phrases like “Keep going!” and “Almost there!,” meant to encourage you to up your daily consumption. Which of course makes them incredibly handy for another recent trend: the “gallon water bottle challenge.” Popularized by writer Danielle Prescod, who chronicled her own water consumption journey on Instagram in the spring, the “challenge” so to speak, isn’t necessarily for anyone but yourself; the premise being that you guzzle a gallon of water (almost four litres) a day.
It’s the 2021 equivalent of "drink at least eight glasses of water a day" — but is it necessary? Water is, of course, essential to survival — not only does it keep you hydrated, it also helps boost energy levels, and literally keeps us moving by helping lubricate our joints. But how much is enough and how much is too much?

It’s the 2021 equivalent of 'drink at least eight glasses of water a day' — but is it necessary?

Fuelled by this question and also an ever-persistent need to down more H20, (I tend to stick to coffee during the workday and am often so locked in to my screen that I typically drink two glasses of water a day max), I tried the gallon challenge. First, I bought my own clear-and-black gallon water bottle (inspired by Jenner’s colour scheme of choice) from Amazon. I filled it up with Toronto’s finest tap water and set to work consuming it.
And I felt like shit.
At least for the first three days, during which time my body proceeded to entirely clear itself out (I'll let you read between the lines) and I felt lethargic and nauseous. Which shouldn’t have come as that big of a surprise, considering I more than quadrupled my water intake, to a minimum of eight glasses of water (and of course, still two coffees — an essential). According to dietitians that I spoke to, this over *ahem* secretion is normal when upping your water consumption by so much, and actually an indicator that you’re probably over hydrating your body
In fact, in extreme, extreme cases, too much water can cause water intoxication. (FYI, there’s no set number or guidelines around how much water is too much.) “What happens is the electrolytes in your body and bloodstream can get diluted,” says Dr. Sidney Radomski, a professor of surgery in urology at Toronto Western Hospital. If your potassium and sodium levels get too low, this can lead to things like seizures or a heart attack. “The electrolytes in our blood are responsible for maintaining our proper heart rate,” adds Abby Langer, a Toronto-based registered dietitian, “and when they’re diluted the heart can’t function properly.” (An example is when people are on ecstasy and drink loads of water, unable to monitor their intake, and end up in the hospital with heart failure. Like I said, extreme circumstances.)
So how much water is ideal? 
While it really depends on the individual, their body, and other factors like where they live (higher temps may mean more water intake), how much they exercise (you lose water via sweat), or if they have any specific health concerns, both Radomski and Langer recommend around two litres or six to eight cups of fluids per day. Fluids can include liquids like coffee (which Langer says actually isn’t dehydrating, but that’s another story) and juice, as well as some of the food that you eat like fruits and vegetables. “Remember that we don’t solely get hydration from fluids, we do get hydration from some of the things we eat as well,” Langer says. (That doesn't include alcohol — remember to drink at least one glass of water for every cocktail.)

You're not going to be healthier if you drink four litres of water a day versus two. There’s a line somewhere and you don't need to cross it.

– ABby Langer, Registered Dietitian
If you decided to take a page from Jenner et al and increase how much water you drink, it’s not going to make you more glowy or miraculously relieve your constipation, Langer says. Contrary to some of those aforementioned beauty adages (and what you may have read in magazines as a tween), any extra water will just be peed out. “It's just a matter of how often you want to go to the bathroom,” Langer says. “You're not going to be healthier if you drink four litres of water a day versus two. There’s a line somewhere and you don't need to cross it.” 
For those who want a concrete — or, er liquid — way to gauge if they’re hydrated, experts recommend the tried and true, if slightly TMI, test. “Check the colour of your pee,” Langer advises. Optimal hydration is a light yellow urine (clear is actually an indicator that you’re over-hydrated); dark yellow means you could use some more fluids. Another trick is to pinch the top of your hand. If your skin snaps back, you’re hydrated; if it tents and doesn’t snap back? “It could mean that you need more fluid," says Langer.
I’m a few months into my experiment of drinking more H20, and some things have changed, and some have remained the same. Thankfully, after about a week, my body became used to the uptake in water consumption (meaning *ahem* fewer trips to the bathroom), but after three weeks of toting a massive water bottle around my apartment and rushing to finish my bottle “on deadline,” I gave up on it altogether, tucking it on top of my washer/dryer for storage.
Four litres a day was just too much for me to commit to personally, and drinking water ended up feeling like a test that I was continuously failing. (And, as Langer asks, “Who wants to carry such a big bottle around?”) Although I haven’t stuck to guzzling a specific amount a day, one positive to come out of this is that it has changed my approach to drinking water as a whole. Now I try to start my day with a glass of water, and have one with every meal and after every coffee, which usually ends up being at least five glasses of water.
And before you ask, yes I’m still checking the colour of my pee. 
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