There’s such a factor as ingesting an excessive amount of water.

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Two years in the past, I had a dialog with my physician that continues to be one of many extra unnerving interactions I’ve ever had. After reviewing the outcomes of a routine blood check, she needed to know if I had lately skilled any of the next: lack of consciousness, dizziness, confusion, or a seizure. No, no, no, and no. Then she needed to know: Did I’ve an altered psychological state? At that time, debatable.

It turned out I had too little sodium in my blood. As the physician and I talked, the wrongdoer turned clear: My wholesome life-style was accountable.

I run or go to the fitness center daily. I attempt to eat nicely. I drink loads of water, particularly after I’m understanding.

Bombarded by public well being warnings in regards to the risks of not ingesting sufficient, I used to be petrified of dehydration. Add in cultural myths like the 8×8 rule—eight glasses of 8 ounces of water a day—and life-style messaging that ingesting extra water will assist me have higher pores and skin, hair, sleep, digestion, you title it, and I used to be knocking again at the very least 3 liters of water every day. That was on high of my morning coffees, a soda right here and there, meals (water crammed!), and every other drinks I occurred to have. Yes, these issues rely towards water consumption.

Altogether, I used to be getting an excessive amount of water. Way, means an excessive amount of.

And now I used to be in peril. In the physique together with water is sodium—an important electrolyte that helps your physique preserve its fluid steadiness, preserves nerve and muscle perform, and retains your coronary heart working, amongst different issues. A wholesome sodium degree is anyplace between 135 and 145 millimoles per liter of blood. Sodium is of course present in meals, and individuals who eat a Western food regimen have a tendency so as to add fairly a bit additional to their meals within the type of desk salt too.

But the physique’s delicate steadiness between water and salt could be quickly thrown out of whack, particularly throughout train. At one finish of the spectrum is dehydration. At the opposite is overhydration and hyponatremia, a probably life-threatening situation.

Hyponatremia happens when an individual’s blood sodium ranges drop under 135 millimoles per liter of blood. If somebody drinks to extra, they successfully dilute their blood sodium ranges. At the identical time, water begins to leak into their physique’s tissues, inflicting them to swell, explains Tamara Hew-Butler, a Texas-based podiatrist who makes a speciality of treating and finding out runners. In extreme instances, the mind can begin to swell, resulting in a few of hyponatremia’s core signs: confusion, dizziness, the lack to talk correctly, and complications.

I used to be coaching for a half-marathon on the time that I used to be identified with hyponatremia, and I used to be simply ingesting 4 liters of water or sports activities drinks a day. My physician was blunt: I used to be ingesting an excessive amount of and never changing the salt I had misplaced in sweat. And whereas I didn’t really feel as if something was incorrect with me, if I didn’t change, I’d be placing myself susceptible to far worse than a headache.

“When the sodium level starts to creep downward, people are more likely to experience more severe symptoms,” mentioned Paul Charlton, an emergency drugs doctor and an affiliate school member on the University of Colorado. An individual can lose consciousness, have seizures, collapse, vomit, and fall right into a coma. In excessive instances, the mind swells a lot that the mind stem herniates—a rupture that’s deadly. All of this may occur within the house of just some hours. Multiple marathon runners and other athletes have died of overhydration lately.

While some individuals could be susceptible to low sodium as a result of they take sure medicines or have an underlying well being drawback, exercise-associated hyponatremia strikes in any other case wholesome individuals. A whole lot of what we all know in regards to the situation comes from finding out ultrarunners and different endurance athletes, in addition to the navy. There’s some proof to suggest that women could also be extra in danger than males, and whereas it’s unclear why, hyponatremia tends to be extra extreme in smaller people purely as a result of it’s easier for them to overconsume fluids relative to their physique mass, mentioned Brendon McDermott, a physiologist on the University of Arkansas and a seasoned marathoner.

It can be unclear how many individuals might expertise hyponatremia, partly as a result of not everybody reveals signs, Charlton mentioned. Interestingly, some research counsel that sure individuals could be low in sodium on a regular basis, whereas others counsel that some individuals won’t have the ability to entry their physique’s sodium shops effectively, tending them toward hyponatremia.

What is abundantly clear, nevertheless, is that when individuals cease ingesting to thirst and as an alternative compel themselves to soak up fluids whereas exercising, their physiology can quickly spiral uncontrolled. (Theoretically, you would additionally overhydrate whereas sitting in your automobile and throwing again Stanley cups filled with water, however it could be exceedingly tough.)

During train, the descent into hyponatremia could be exacerbated specifically methods, Hew-Butler mentioned, not least by sweating out salts. But there’s a hormonal side too: Vasopressin, an antidiuretic hormone, ramps up throughout train, and particularly when it’s sizzling.

“Your body’s like, ‘Oh my God, I’m losing water. I’m not going to pee it out,’ ” Hew-Butler mentioned. By suppressing the decision of nature when you’re dropping fluid by means of sweat, the physique is attempting to keep up that delicate water-to-salt ratio and preserve every little thing working the best way it ought to, she defined.

In different phrases, the physique begins attempting to retain fluid. Importantly, subbing out water for sports activities drinks is just not going to chop it: “It functionally makes very little difference in terms of people’s outcome,” Charlton mentioned. He and different consultants I spoke to all agreed that the majority sports activities drinks ought to be handled as water. (For context, most industrial sports activities drinks include round 10 % of an individual’s really helpful day by day sodium—a 20-ounce bottle of Gatorade Thirst Quencher, for instance, has 270 milligrams, or about 11 %, whereas a 12-ounce bottle of Powerade comprises 240 milligrams of sodium, which is 10 %.) So for those who begin chugging sports activities drinks or water halfway by means of a run, then you may shortly swell your cells.

“That’s why sometimes people get in more trouble during exercise,” Hew-Butler mentioned. “They preload and they keep loading.”

Confoundingly, hyponatremia’s early medical presentation—dizziness, headache, confusion—seems virtually precisely the identical as that of dehydration or warmth exhaustion. Hyponatremia could be confirmed solely by a blood check, and whereas medical tents at massive sports activities occasions and emergency rooms have the package to have the ability to shortly verify individuals’s sodium ranges, your common Jane—me!—won’t understand the true nature of their drawback. And that may make issues worse, quick.

In an rising variety of instances, Charlton mentioned, individuals who don’t match the everyday mildew for acute or exercise-associated hyponatremia are being identified with the situation.

If somebody is out climbing or taking part in in a highschool soccer recreation, and even simply doing a little gardening in sizzling climate, they is perhaps tempted to drink quite a lot of water even when they aren’t thirsty in a bid to keep away from dehydration or merely to chill down, he mentioned, unwittingly endangering themself within the course of.

Charlton recalled the case of a Japanese woman who was acting on an outside stage on a sizzling day. She collapsed and had a five-minute seizure after her act. It turned out that, fearful about warmth damage and following public well being steering to drink plenty of water, she had drunk about 4 liters of liquid throughout her present. When staffers took her blood on the hospital, they realized that her sodium degree was 117.

“It was not clear at the beginning [that she had hyponatremia] because she did not fit their profile,” Charlton mentioned. “She wasn’t an ultrarunner. She wasn’t engaged in regular high-stress activities.”

She was merely attempting to maintain herself. And doing that earlier than you’re thirsty can result in hassle.

“You hear a lot about, like, thirst is inadequate, and if you get thirsty, it’s too late,” Hew-Butler mentioned. “But thirst is a biological mechanism that’s been conserved for 700 million years,” she added. “It’s not defective when you exercise.”

This resonated with me. I had all the time thought that if I felt thirsty throughout train, and particularly in sizzling climate, then I used to be in hassle—dehydrated and susceptible to warmth exhaustion. I by no means as soon as thought of that I won’t really feel thirsty as a result of I had drunk an excessive amount of.

It’s true that dehydration and warmth exhaustion are extra widespread than hyponatremia—a survey of energetic navy personnel in 2024 discovered simply 134 cases of exertional hyponatremia, whereas there have been 471 cases of heatstroke and a couple of,380 instances of warmth exhaustion, for instance.

But McDermott, the University of Arkansas physiologist, famous that whereas dehydration alone is unlikely to kill you, for those who develop hyponatremia and it goes unchecked, then it might quickly be lethal in and of itself. “There should be education on hyponatremia, equal to dehydration,” he mentioned.

He and different consultants I spoke to for this story mentioned that individuals participating in sporting occasions ought to be issued steering on overhydration, and that public well being messaging should be clearer in regards to the particular risks of hyponatremia. Hew-Butler prompt that occasions like marathons ought to truly restrict their water and sports activities drink stations to discourage overconsumption.

Charlton argues that public well being officers should be cognizant of hyponatremia once they make suggestions for coping with hotter climate (one thing we’ll solely have increasingly more of resulting from local weather change). “Probably, as more people are experiencing heat with climate change, there is just going to be a different profile of person that we have to look at these issues in,” he mentioned.

If somebody is suspected of getting hyponatremia—a situation that’s, once more, difficult to diagnose—the primary, smartest thing they’ll do is cease ingesting water, Hew-Butler mentioned. In my case, my physician advised me to drink not more than a liter of fluid—water, espresso, soda, no matter—for a number of days with the intention to deliver my sodium ranges again to a wholesome baseline. As an individual accustomed to ingesting 3 or 4 liters a day, I discovered that slicing again was exhausting.

More acute instances require extra intervention: In some cases, docs would possibly inject a bit very salty saline into an individual’s blood to attempt to deliver up their sodium ranges. If the affected person is ready to swallow, they could make them drink 1 / 4 cup of water containing 4 dissolved bouillon cubes—which actually sounds not unhealthy. What about salt dietary supplements? There is mounting proof that sodium supplements like salt tablets aren’t sufficient to stop hyponatremia throughout intense train, though McDermott mentioned they seemingly wouldn’t damage both.

At the identical time, there’s no single recommended amount of water that everybody ought to drink whereas understanding, Hew-Butler mentioned. In truth, you may calculate how a lot fluid you lose whereas exercising by weighing your self earlier than and after an hour of your chosen exercise. The distinction signifies the water weight shed by means of sweat. Apart from that, she and the opposite consultants I spoke to for this piece all had the identical suggestions: Drink whenever you’re thirsty. Stop whenever you’re not. Eat salt. And if you end up craving salt on a long term, purchase a bag of pretzels or chips.

Have I realized my lesson? Sort of. I’ve been identified with hyponatremia greater than as soon as since that first occasion; my physician thinks I’m a kind of people who simply run a bit low on sodium. But I’ve made modifications. I make a acutely aware effort to note my thirst whereas exercising. When I do know I’m going to be sweating rather a lot, I additionally take an electrolyte combine known as LMNT, which I order on-line; it comprises virtually half of my day by day really helpful sodium. I additionally really feel fully at liberty with the desk salt. It’s working for me.

And as Hew-Butler advised me, hydration is “an experiment of one.” Another technique to put it: We stay in a world filled with large water bottles. We fetishize a straightforward well being repair. But, significantly for those who’re an athlete, take heed to your individual thirst cues and simply say no to massive hydration.

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