- 7 Signs You’re Drinking Too Much Water
- How much water to drink
- How much water is too much?
- What happens if you drink too much water?
- The Fix
- Is There Such A Thing As Drinking Too Much Water?
- Water Consumption: Healthy Levels vs. Overconsumption
- Signs and Risks of Overhydration
- How Can Overhydration Happen?
- Hydrating and Avoiding Water Poisoning
- Drinking too much water could be surprisingly hazardous to your health
- Is drinking too much water bad for you?
- Can You Drink Too Much Water?
- How much water do you actually need?
- But overhydration?
- So what is ‘hyponatremia?’
- Preventing overhydration and hyponatremia
- Chugging Water All the Time? How to Avoid Overhydration
- What is proper hydration?
- How much water can we handle?
- What happens when you drink too much water?
- Hyponatremia vs. water intoxication
- Who’s at risk?
- Signs you may need to cut back
- How to stay hydrated without overdoing it
- Special considerations
7 Signs You’re Drinking Too Much Water
Thirst is the best indicator that you need water, Statt explains. One study in the Proceedings of the National Academy of Sciences found that our swallow reflex diminishes once we’ve had enough to drink. So, lack of thirst could mean you’ve hydrated enough. That being said, the National Academies of Sciences, Engineering, and Medicine recommends women drink 2.7 liters of water each day and that men drink 3.7 liters each day.
Many of these signs don’t indicate over-hydration in of themselves, so also check your urine color and the frequency with which you’re going to the bathroom. If you’ve over-hydrated, Statt recommends avoiding water and instead having a sports drink, which can replenish your electrolytes. If you’re experiencing symptoms of hyponatremia, you’ll want to go to the doctor’s to get a saltwater injection and any other treatments necessary to restore your body’s electrolyte balance.
Morgan Statt, Health and Safety Investigator at ConsumerSafety.org
Dr. Sangeeta Mahajan, MD, urogynecologist at the University Hospital Case Medical Center
We’re always being told to drink more water – but is it possible to overhydrate? How much water is too much? And what happens if you down bottles of the stuff?
Now that drinking water is officially a type of social media influencing, we reckoned it’s time to get some definitive answers.
No, you still probably aren’t drinking enough water, and no, you definitely shouldn’t ditch that massive carafe on your desk out of fear you could drown your insides.
The general rule is pretty simple: drink water when you feel like it, and if you feel like you’re drinking too much, take a break.
How much water to drink
You’ve likely been told to drink six to eight glasses of water a day. While some have suggested that this is a made up figure plucked out of thin air, the NHS does say this is a good amount to aim for.
‘Our body needs water or other fluids to work properly and to avoid dehydration,’ says the official NHS guidance. ‘That’s why it’s important to drink enough fluids.
‘In climates such as the UK’s, we should drink about 1.2 litres (six to eight glasses) of fluid every day to stop us getting dehydrated. In hotter climates, the body needs more than this. We also get some fluid from the food we eat.’
Here’s a handy thing about the human body: it has a solid system for regulating how much water to drink.
When your body’s water content drops, you’ll feel thirsty. When you feel thirsty, you should drink some water.
Some people find it beneficial to sip throughout the day to preempt feelings of thirst, but whether you do this is a personal choice. Trust your body, aim for six to eight glasses, and you should be golden.
Additional water will need to be consumed if you’re exercising, sweating a lot, or are poorly and at risk of dehydration.
How much water is too much?
It’s tricky to drink too much water without realising, as this would require ignoring your body’s signals to stop downing the stuff.
But it is possible to drink too much – and this is normally to do with drinking water too quickly in a short period of time.
Dr. Imogen Bexfield, Doctor and Medical Director at White Swan Aesthetics, tells Metro.co.uk: ‘It’s not so much about the total amount you would consume throughout an entire day but more about the the amount you drink per hour.
‘Drinking too much water in a short period overwhelms your kidneys so they can’t process and eliminate the water fast enough which drives your blood levels of sodium too low.
‘If you aren’t sure about how much is “too much” listen to your body – it will tell you if you need to hydrate.
‘It’s also good to keep an eye on the colour of your pee as this can be an indication of over-hydration. Your pee should be a pale yellow colour—if it’s darker than that, drink some water, and if it’s lighter, hold off until you feel thirsty again.
‘Though it’s not as common as dehydration, it is possible to drink too much fluid. Over-hydration can happen when you take in more water than your body can process and get rid of, and it can lead to serious problems.’
Your kidney is able to eliminate around 28 litres of water a day (which is likely more than you’re drinking), but this amount has to be drunk over the course of a full day. Your body isn’t able to get rid of more than a litre of water per hour.
This suggests that as a general rule, drinking more than a litre of water an hour is ‘too much’. It’s far better to spread your water intake throughout the day than chugging down a massive bottle in one go.
What happens if you drink too much water?
Imogen explains: ‘Watering down your blood can make it harder to carry nutrients, send brain signals and control the muscles in your body.’
‘If you consume too much in too short period, over hydration can become a serious issue and you could be at risk of hyponatremia.
‘This is when the sodium in your body becomes weaker and less effective, when this happens, it increases your body’s water levels, as a result your cells to begin to swell.
‘Although very rare, hyponatremia can cause muscle weakness, cramps, and seizures.’
The effects of hyponatremia can be lethal.
Excess water can cause brain cells to swell, increasing the pressure inside the skull. At first this can cause headaches and nausea, then confusion, difficulty breathing, and muscle weakness.
In severe cases, excess fluid can affect the central nervous system, leading to seizures, brain damage, coma, and even death.
As we mentioned, though, hyponatremia is rare, and it would be difficult to overhydrate without realising.
Listen to your body. When you’re thirsty, drink water, when you’re not, stop, and make sure to keep a bottle with you if you’re planning to sweat. Easy.
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Is There Such A Thing As Drinking Too Much Water?
Overhydration: does that sound like an absurd idea? Most people find it hard enough to drink water daily and stay properly hydrated… but can it be possible to drink too much water? The truth is, this phenomenon is real and has the potential to lead to adverse health effects. Overhydration, also known as “water intoxication,” is a condition that develops from consuming an extreme quantity of water too quickly. Find out the symptoms of water intoxication, why it happens, and how to avoid it.
Water Consumption: Healthy Levels vs. Overconsumption
Water intoxication has a few different names: hyperhydration, water poisoning, water toxemia and hyponatremia all refer to the same reaction. It’s pretty straightforward: water poisoning occurs when you drink too much water. But how much is too much? Both the quantity and the rate of consumption are factors in overhydration. It can be hard to determine a “recommended” level of water intake that applies to everyone since individual activity level and body weight are important factors. Should an inactive young woman drink as much water as a professional male basketball player? Of course not! In general, women should drink 91 ounces of water a day while men should consume about 125 ounces. These amounts are recommended by The Institute of Medicine (IOM) and change depending on your build and lifestyle.
Signs and Risks of Overhydration
Excessive water consumption can happen for a variety of reasons. Too much water consumption can dilute the normal sodium content in blood. When your sodium levels sink too low, hyponatremia occurs. This means the water level in the body tries to equalize with that of the sodium level, swelling cells. This can cause a number of issues, including nausea, muscle cramps, seizures, and swelling in the brain. Hyponatremia can result in serious consequences, such as seizures, brain damage and even death. Deaths from overhydration are easily preventable through simple awareness.
Initial signs of excessive water consumption and swelling cells are headaches, nausea and vomiting. More serious symptoms include:
- Double vision
- Muscle cramping
- Difficulty breathing
- Issues processing sensory information
How Can Overhydration Happen?
Most often, cases of deaths due to water intoxication have been reported in endurance athletes and soldiers. However, there are a number of reasons why a person may drink too much water or drink too much very quickly. Those who are trying to lose weight quickly or following a strict diet may drink more water than needed to feel full. Periods of intense exercise or hot weather may also cause overconsumption of water. Some medications can cause dry mouth and make you feel extra thirsty, even if they aren’t actually dehydrated. These situations could lead to overhydration. Those who feel constantly thirsty may want to check with a doctor. This can be a symptom of diabetes and is also found in those with severe anemia.
Hydrating and Avoiding Water Poisoning
Adults and children should be aware that drinking water is essential, but problems can arise from too much of a good thing. Caregivers for elderly individuals or those on medications need to be aware of the possibility of water poisoning and watch for significant changes in thirst. If you’re experiencing extreme thirst or showing symptoms related to overhydration, find an urgent care clinic near you for assistance.
Drinking too much water could be surprisingly hazardous to your health
- Drinking too much water can be unhealthy and even lead to death in extreme cases.
- When you drink more water than your kidneys can handle, you can upset the balance of sodium levels in your blood — this is called water intoxication.
- Check out the video above to find how this imbalance can wreak havoc on your brain and body.
We couldn’t live without water. But if we drink too much, it can wreak havoc on our brain and body. Drinking more water than your kidneys can process can throw your blood sodium levels out of balance. That’s called water intoxication. And in extreme cases, it can cause brain damage, comas, and even death.
Following is a transcript of the video.
What do you think of when you hear the word poison? Arsenic? Cyanide? How about water?
Life couldn’t exist without water. But in the right circumstance… Water can be as dangerous as any poison.
Here’s what happens when you drink too much water.
Your kidneys filter out excess waste and water from your bloodstream. But they can only process 800-1,000 mL of water an hour. And if you somehow manage to drink more than that without throwing up, you can run into trouble. Because you’re drinking faster than your kidneys can process it. So the excess ends up in your cells.
Normally, your cells are surrounded by a carefully-balanced solution of sodium and water, which flows in and out through tiny holes in the cellular membrane, so it keeps the sodium concentration both in and out of the cell balanced.
But when you drink too much water, the sodium solution gets diluted. It’s not salty enough. So some of that extra water rushes into the cell to restore balance and that causes it to swell up.
Doctors call this water intoxication and it’s a big problem. Now, most of your cells can handle the swelling to a degree since soft, flexible tissue like fat and muscle can stretch.
But for the cells in your brain, it’s another story, because your skull isn’t stretchy.
It’s bone. It’s hard — like a rock.
So, as your brain swells, it builds up the pressure in your head.
At first, you might experience headaches, confusion, or drowsiness.
But as the pressure increases, you risk brain damage, coma, and even death. And it could all be over in less than ten hours.
A 64-year-old woman, for example, died the same evening after drinking between 30-40 glasses of water. And a group of US Army trainees suffered vomiting and seizes after downing over 2 liters per hour after a tough day of training.
But it’s marathon runners who need to be especially careful. A study found that 1 in 6 marathon runners develop at least mild water intoxication because the race stresses their body, including the kidneys. So, they don’t excrete water as efficiently, which can cause water to back up into the blood more easily.
People with certain kidney issues are also vulnerable since they can’t properly process water and the problem isn’t unique to water.
For example, the same thing can happen if you down too much beer at once. That’s called potomania.
The good news is that there’s an easy way to stay safe. The average healthy adult needs somewhere around 3-4 liters of water a day. And since this can come from food and other drinks too, drink when you’re thirsty, and then stop.
Is drinking too much water bad for you?
Modern health trends come and go, but one piece of advice that doesn’t ever seem to change is that we should all be drinking as much water as possible. As it turns out, though, there are hidden dangers to this most innocuous of activities – the spectre of “water intoxication”, hydration’s potential sting in the tail.
Headaches, nausea, fatigue – all of these symptoms are associated with dehydration but can also rear their heads if you’re over-hydrated, as it turns out. The scientific word for the issue is hyponatremia but the condition is really rare, especially if you’re not an endurance athlete.
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Upward and onward. 📸: @sin_rutas on the Annapurna Circuit Trek, Nepal
What is over-hydration?
Essentially, over-hydration is when you take on more fluid than your kidneys can process and remove. It can be dangerous and even fatal in the most extreme cases. “Watering down your blood it harder to carry nutrients, send brain signals and control the muscles,” says Harry Aitken, a qualified sports scientist at Auster.
Over-hydration can particularly crop up during exercise, as people try to gulp down the water they’re losing through sweat. “People have a tendency to replace the water but forget the sodium losses,” say Dr Ricardo Da Costa, a nutrition lecturer at Monash University. Da Costa says that rehydration is all well and good, but without sodium to balance the equation, the change to the composition of our plasma can be problematic.The amount of water people should drink depends on their age, weight, physical activity and how hot the weather is (Thinkstock/PA)
The risk of over-hydration is still relatively slim for most people, though. As Johanna Hignett, an advisor to the Natural Hydration Council, explains: “You would need to drink extremely large quantities, in the order of five litres or more within an hour” to be at risk of hyponatremia. In normal life you’re unlikely to be chugging as much as that.
What are the symptoms?
Hyponatremia causes the sodium in your body to become diluted, and when this happens, your body’s water levels rise, causing your cells to begin to swell. This swelling can cause many signs and symptoms, from mild to life-threatening.You may experience nausea (Thinkstock/PA)
A person who is consistently drinking too much water may experience nausea and vomiting, headaches, confusion and loss of energy. In more extreme cases, it can cause muscle weakness, spasms or cramps, seizures and can even result in coma.
Experts advise that anyone who develops severe signs and symptoms of hyponatremia should seek immediate emergency care.
How can you avoid over-hydration?
The steps to avoid reaching the point of over-hydration involve some relatively obvious reversals of normal practice. If you’re monitoring the colour of your urine, as some people do, you should be aiming for a light yellow colour, rather than shooting for as clear pee as possible – which many people assume means the peak of hydration.
Urine shouldn’t be entirely clear and, if it is, you might be drinking more water than you need. Hignett says the ideal shade for most people is “a pale straw colour”.
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Are you drinking enough? You can tell if you are dehydrated by looking at your pee! Check out our latest blog post on hydration. #hydration #water #urinecolour #pee #peecolour #dietitian #dietitianslife
People who drink too much water while taking part in marathons, ultra marathons, triathlons and other long-distance, high-intensity activities are at an increased risk of hyponatremia, so if you’re rehydrating after exercise, consider taking it slower than usual.
If you notice yourself taking time to return to normal service after working out, try drinking a sports drink, as the sodium content can help you to find your balance again.
At the 2002 Boston Marathon, a study found that 13% of participants demonstrated the symptoms of hyponatremia, proving that, while serious results are extremely rare, the issue is still common – especially at sporting events.Marathon runners may be more at risk (Thinkstock/PA)
There’s a reason that daily water recommendations have both lower and upper limits, so you should try to stick to them in normal, day-to-day life. NHS guidance advises that we drink six to eight glasses of fluid a day, although food can also contribute to this total.
It makes sense, therefore, that drinking 15 cups of water a day might not be sensible. A safe limit is one litre of liquid per hour, as this is roughly what your kidneys are able to process normally.
Finally, it may sound obvious, but the body already has a built-in system to help you know how much to drink – thirst. If you keep drinking and never stop feeling thirsty, talk to your doctor, as this could be a sign that something isn’t quite right. But, for most people, drinking until you’re no longer thirsty, then stopping, will keep your levels in check.
I love drinking water first thing in the morning it’s like I can really feel this raisin turn back into a grape
— Trinity (@trinitycormier2) December 21, 2018
The risks of over-hydration may be low, but it’s worth knowing that the condition is possible, especially if you’re a budding athlete with a marathon to run in 2019. With these tips in mind though, you should be safe from the little-known problem of hyponatremia.
– Press Association
Can You Drink Too Much Water?
You probably can’t count the number of times you’ve been told to drink lots of water, stay hydrated, drink before you get thirsty, etc. — especially when you’re exercising. And at face value — and further — this is solid advice. Your body needs water to perform its basic functions, the sweat you lose when you exercise needs to be replaced — you get the picture.
But what about the opposite end of the spectrum? Is it possible to drink too much water in a day? Is that a thing?
Well, the short answer is actually yes. If you drink too much water, you can cause sodium (salt) levels in your body to be diluted to a dangerously low level, disrupting your electrolyte balance– and that can have serious effects on your health if not corrected.
But how do you get to that point? Why? How much water is too much?
How much water do you actually need?
Before you dive into the details — and they get a bit heavy — take a minute and review the relationship between water and your body. Firstly, alongside food and oxygen, water is important to survival. With as much as 60% of your total body weight coming from water, it’s actually the principal element making up you.
Water helps you regulate your body temperature (think sweating), helps to transport nutrients through your bloodstream, flushes waste out through urine, and acts as “padding” for all of your organs — just to name a few functions. Water has its fingers into literally every part of your body, from the cell-level up — it’s so important that if you don’t drink enough, the effects can be lethal in just days.
When you don’t drink enough water, you get dehydrated. Even mild dehydration can make you feel tired, reduce your cognitive awareness, and decrease your exercise performance. And as already mentioned, severe dehydration can kill you.
Currently, the National Academies of Sciences, Engineering, and Medicine offer some fairly concrete recommendations for regular individuals:
- Men should drink approximately 3.7 liters (125 ounces) of fluids each day; and
- Women should drink about 2.7 liters (91 ounces) per day.
But keep in mind, these recommendations are for ordinary individuals going about their regular day to day — not athletes or exercising people. So that being said, you may need to increase your intake of water when you are exercising intensely and in hot or humid weather. Pregnant or breastfeeding women may also need to increase water intake, as hydration needs differ.
So that’s getting enough water, and too little, but what about drinking too much? Again — drinking too much water is possible.
In 2003, a 64 year-old woman was found dead in her home. The night before she passed, she drank water in tremendous quantities — an estimated 30-40 glasses, interspersed with repeated vomiting. She became increasingly disoriented and distressed, yelling about how she had not drank enough water. After declining to obtain medical attention, she went to bed and died at some point during her sleep.
Given that the woman had no relevant previous medical history, a postmortem exam was performed 6 hours later. Blood toxicology ruled out many causes of death, and it was ultimately determined that she had died of “hyponatremia as a result of acute water intoxication.”
Another study was performed on ultradistance triathletes. Included in this study were 605 of 660 athletes who had entered into a New Zealand Ironman triathlon. Prior to the race, they were weighed and had blood drawn for a measurement of their blood plasma sodium concentrations. The lab results of just 330 of the race finishers was available following the conclusion of the study.
Of these 330, 58 (18%) were hyponatremic (low sodium levels); of these, just 18 received medical attention; 11 of these 18 were severely hyponatremic; and 7 of these 11 have symptoms of severe hyponatremia. The study concluded that while hyponatremia is a common finding in distance athletes, it’s usually non-symptomatic — and in the case of 73% of the severely hyponatremic athletes studied, fluid overload was the cause.
There are many other cases that can be reviewed — but the answer is clear and concrete: you can drink too much water.
How does this happen?
Wait, so how does that work? To understand that, you need to know how your body handles water, salt, and waste materials.
Normally your kidneys act as “filters” of waste material. Your blood is carried to your kidneys by way of the renal arteries. As it passes through the kidneys, excess fluid and waste material is removed by little units called nephrons. Some of these materials being filtered include things like sodium, among others. Whatever your body still needs is reabsorbed into the bloodstream — the rest is sent to your ureters to be removed in your urine.
But, when you drink fluids in excess, you can overwhelm your kidneys’ ability to excrete it all. This leads to your body retaining fluid and causes something called hyponatremia — don’t worry about that term right now — it’ll be discussed shortly. If you have pre-existing kidney problems, your kidneys are at an even greater risk for this condition, and you may be more susceptible.
When you overwhelm your body’s ability to excrete the water and waste products you take in, you develop water intoxication — the same condition that killed the 64-year-old woman mentioned earlier. Water intoxication causes disturbances in the electrolyte balance of your body, causing a life-threatening condition known as hyponatremia. With a rapid decrease the sodium levels in your blood, relative to the amount of water, symptoms can quickly develop:
- Early symptoms can include confusion, disorientation, nausea and vomiting, as well as changes in your mental state, or symptoms of psychosis.
- Later symptoms can develop, if left untreated, into seizures, coma, and eventually death.
So what is ‘hyponatremia?’
Now that it’s been mentioned several times, what’s hyponatremia? Essentially, it’s a low salt concentration in your body and is the most frequent dyselectrolytemia, or abnormal electrolyte disorder. It’s classified quantifiably as a decrease in serum sodium concentration of below 136 mmol/liter of blood.
But it’s not just a problem of “low sodium” — you don’t typically get hyponatremia by not eating enough salty foods. Hyponatremia is a relative disorder — the amount of sodium in comparison to the amount of water. There are actually 3 primary types of hyponatremia, each with different typical causes:
Euvolemic hyponatremia can also be called dilutional hyponatremia, and is the kind we’re talking about. It’s typically caused by polydipsia — excessive thirst, causing you drink more water than normal. But again, this can also happen as a result of thinking that you can’t drink too much.
The ordinary treatment is to treat the cause — often diabetes, mental illness, or brain injury.
Hypervolemic hyponatremia occurs when both water and salt increase, but the water increase is relatively greater than the sodium. It usually happens as a result of health issues that cause water and salt retention, like heart failure or cirrhosis.
In those cases, treatment is usually fluid restriction and administering a diuretic, a medication that forces fluid to be excreted through urination, to remove body water.
Hypovolemic hyponatremia — if you have any knowledge of medical terminology — is the opposite of hypervolemic hyponatremia. In this case, both total body sodium and water have decreased, but the salt levels of have decreased comparatively more.
This type of hyponatremia happens when sodium-containing bodily fluids are lost — think vomiting and diarrhea during prolonged illness. It can also happen with some kidney disease and prescribed medications — like those diuretics mentioned earlier. Treatment varies by severity, but involves replacing both the fluid and sodium lost through administration of medications like 0.9% Normal Saline.
Preventing overhydration and hyponatremia
So since it’s been established that you can drink too much water — with potentially deadly consequences — how can you can avoid it? Drinking enough water, but not too much, is relatively simple:
- Drink according to thirst. Your body knows when it needs water, so drink when you get thirsty, not before. If you’re sedentary, shoot for the numbers mentioned earlier. If you’re active, use those numbers as a guideline, but expect to drink more (especially if you’re taking a diuretic). And time it according to feelings of thirst.
- Estimate hourly sweat loss. A slightly more complex method, if you exercise for prolonged periods, in hot or humid weather, or compete in sports, you can try this out. Weigh yourself before the exercise, drink according to thirst during the event, then weigh yourself afterward. Your goal is to be the same or slightly less weight — if you weigh more, than you drank more water than necessary. This strategy may more applicable if you compete in sports (i.e. football), where you have a scale available that you can use each hour to guide your fluid intake.
- Avoid excess fluid consumption. This one’s simple — if you’re not thirsty, don’t drink excess fluids. Otherwise, you might experience nausea or even vomiting. Of course, that doesn’t mean don’t drink any fluid at all, but simply don’t drink if you’re not thirsty.
Likewise, there are a few things you can keep an eye on as simple “markers” to determine if you’re drinking enough: if you aren’t thirsty (or often thirsty) or if your urine is colorless or faintly yellow — you’re likely drinking enough water.
Despite common knowledge, it is possible to overhydrate. This can lead to as little as some confusion, to as far as coma or death. But, simple measures can be taken to ensure that you are both:
- Drinking enough; and
- Not drinking too much.
Essentially, listen to what your body is telling you. Water consumption is important to your overall health, and thus your body composition goals. Drink whenever you get thirsty, drink enough to support your activity levels — but don’t “over-drink.” You’ll thank us later.
Matthew Seiltz is a writer and lifelong strength and fitness enthusiast. When not writing or working out, he can be found with a book or spending time with his wife and sons outdoors.
Chugging Water All the Time? How to Avoid Overhydration
It’s easy to believe that when it comes to hydration, more is always better.
We’ve all heard that the body is made mostly of water and that we should drink about eight glasses of water a day.
We’re told that drinking copious amounts of water can clear our skin, heal our colds, and aid in weight loss. And everyone seems to own a giant reusable water bottle these days, refilling constantly. So, shouldn’t we be chugging H2O at every opportunity?
Although getting enough water is very important for your overall health, it’s also possible (though uncommon) to consume too much.
Dehydration may always be in the spotlight, but overhydration also has some serious adverse health effects.
Here’s a look at what happens when you drink too much water, who’s at risk, and how to ensure you stay properly — but not overly — hydrated.
What is proper hydration?
Staying hydrated is important for bodily functions like blood pressure, heart rate, muscle performance, and cognition.
However, “proper hydration” is notoriously difficult to define. Fluid needs vary by age, sex, diet, activity level, and even the weather.
Health conditions like kidney disease and pregnancy can also alter the amount of water a person should drink each day. Certain medications can affect the body’s fluid balance, too. Even your own individual hydration needs can change from day to day.
In general, most experts recommend calculating half your weight and drinking that number of ounces per day. For example, a 150-pound person could strive for a daily total of 75 ounces (oz.), or 2.2 liters (L).
The Dietary Reference Intake from the Institute of Medicine also offers guidelines for adequate water consumption for children and adults.
Adequate daily water intake by age
These target amounts include not only water and other fluids you drink, but water from food sources as well. A number of foods can provide liquids. Foods like soups and popsicles are recognizable sources, but less obvious items like fruits, vegetables, and dairy products also contain significant amounts of water.
So, you don’t need to only chug H2O to stay hydrated. In fact, other fluids can contain necessary nutrients you don’t get from regular water that are important for your health.
How much water can we handle?
While we all need plenty of water to maintain good health, the body has its limits. In rare cases, overloading on fluids can come with dangerous consequences.
So, how much is too much? There’s no hard number, since factors like age and preexisting health conditions can play a role, but there is a general limit.
“A normal person with normal kidneys can drink as much as 17 liters of water (34 16-oz. bottles) if taken in slowly without changing their serum sodium,” says nephrologist Dr. John Maesaka.
“The kidneys will excrete all of the excess water fairly promptly,” Maesaka says. However, the general rule is that the kidneys can only excrete about 1 liter an hour. So the speed at which someone drinks water can also change the body’s tolerance for excess water.
If you drink too much too fast, or your kidneys don’t work properly, you may reach a state of overhydration sooner.
What happens when you drink too much water?
The body strives to constantly maintain a state of balance. One part of this is the ratio of fluid to electrolytes in the bloodstream.
We all need certain amounts of electrolytes like sodium, potassium, chloride, and magnesium in our bloodstream to keep our muscles contracting, nervous system functioning, and body’s acid-base levels in check.
When you drink too much water, it can disrupt this delicate ratio and throw off the balance — which is, unsurprisingly, not a good thing.
The electrolyte of most concern with overhydration is sodium. Too much fluid will dilute the amount of sodium in the bloodstream, leading to abnormally low levels, called hyponatremia.
Symptoms of hyponatremia may be mild at first, such as a feeling of nausea or bloating. Symptoms can become severe, especially when sodium levels suddenly drop. Serious symptoms include:
- unsteady gait
Hyponatremia vs. water intoxication
You may have heard the term “water intoxication” or “water poisoning,” but these aren’t the same thing as hyponatremia.
“Hyponatremia merely means the serum sodium is low, defined as less than 135 mEq/liter, but water intoxication means the patient is symptomatic from low sodium,” notes Maesaka.
Left untreated, water intoxication can lead to brain disturbances, since without sodium to regulate the balance of fluid within cells, the brain can swell to a dangerous degree. Depending on the level of swelling, water intoxication can result in coma or even death.
It’s rare and quite difficult to drink enough water to get to this point, but dying from drinking too much water is entirely possible.
Who’s at risk?
If you’re healthy, it’s unlikely that you’ll develop serious problems as a result of drinking too much water.
“Our kidneys do an excellent job at removing excess fluids from our body with the process of urination,” says dietitian Jen Hernandez, RDN, LD, who specializes in treating kidney disease.
If you’re drinking large amounts of water in an effort to stay hydrated, it’s more likely you’ll need frequent trips to the bathroom than a trip to the ER.
Still, certain groups of people have a higher risk for hyponatremia and water intoxication. One such group is people with kidney disease, since the kidneys regulate the balance of fluid and minerals.
“People with late-stage kidney disease can be at risk for overhydration, as their kidneys are unable to release the excessive water,” says Hernandez.
Overhydration can also occur in athletes, especially those participating in endurance events, such as marathons, or in hot weather.
“Athletes who train for several hours or outdoors are typically at higher risk of overhydration by not replacing electrolytes like potassium and sodium,” says Hernandez.
Athletes should be mindful that electrolytes lost through sweat can’t be replaced with water alone. An electrolyte replacement beverage may be a better choice than water during lengthy bouts of exercise.
Signs you may need to cut back
Initial signs of overhydration may be as simple as changes in your bathroom habits. If you find yourself needing to urinate so often that it disrupts your life, or if you have to go multiple times during the night, it may be time to reduce your intake.
Urine that’s completely colorless is another indicator you might be overdoing it.
Symptoms that indicate a more serious overhydration problem include those associated with hyponatremia, such as:
- loss of coordination
If you’re concerned, talk to your doctor. They can perform a blood test to check your serum sodium levels and recommend treatment if needed.
How to stay hydrated without overdoing it
It’s debatable whether there’s truth to the adage, “If you’re thirsty, you’re already dehydrated.” Still, it’s certainly a good idea to drink when you feel thirsty and to choose water as often as possible. Just make sure you pace yourself.
“Aim to sip water slowly throughout the day rather than waiting too long and downing an entire bottle or glass at once,” says Hernandez. Be especially careful after a long and sweaty workout. Even if your thirst feels unquenchable, resist the urge to chug bottle after bottle.
To hit the sweet spot for fluid intake, some people find it helpful to fill a bottle with their recommended adequate intake and drink it steadily throughout the day. This may be especially useful for those who struggle to drink enough, or simply to get a visual of an appropriate daily amount.
For many, however, it’s more practical to monitor the body for signs of adequate hydration than to focus on hitting a specific number of liters per day.
Signs you’re properly hydrated
- frequent (but not excessive) urination
- pale yellow urine
- ability to produce sweat
- normal skin elasticity (skin bounces back when pinched)
- feeling satiated, not thirsty
If you have kidney disease or another condition that affects your body’s ability to excrete excess water, it’s important to follow the fluid intake guidelines from your doctor. They can best assess your individual health and needs. You may be instructed to limit your water intake to prevent a dangerous electrolyte imbalance.
Additionally, if you’re an athlete — especially participating in endurance events like marathon running or long-range cycling — your hydration needs on race day look different than on a regular day.
“Having an individualized hydration plan in place prior to racing a longer event is important,” says sports medicine doctor John Martinez, MD, who serves as an onsite physician for Ironman triathlons.
“Know your relative sweat rates and how much you need to drink to maintain normal hydration. The best way is to measure body weight before and after exercise. The change in weight is a rough estimate about the amount of fluid lost in sweat, urine, and respiration. Each pound of weight loss is approximately 1 pint (16 ounces) of fluid loss.”
While it’s important to know your sweat rates, you don’t need to completely obsess over hydration while exercising.
“Current recommendations are to drink for thirst,” says Martinez. “You don’t need to drink at every aid station during a race if you are not thirsty.”
Be mindful, but don’t overthink it.
Finally, while it’s normal to be occasionally thirsty throughout the day (especially in hot weather), if you notice you feel the need to drink constantly, see your doctor. This may be a sign of an underlying condition that needs treatment.
Sarah Garone, NDTR, is a nutritionist, freelance health writer, and food blogger. She lives with her husband and three children in Mesa, Arizona. Find her sharing down-to-earth health and nutrition info and (mostly) healthy recipes at A Love Letter to Food.
Tamara Hew-Butler, PhD, FACSM, is Associate Professor of Exercise and Sports Studies at Wayne State University
With August football practice fast approaching, every coach’s favorite cheer will be to “stay hydrated” and “keep urine clear” during the summer heat.
In 2017, a University of Texas football coach created a urine-based “Longhorn Football Hydration Chart,” which labeled players with yellow urine as “selfish teammates” and those with brown urine as “bad guys.” This “hydration shaming” practice has permeated high school sports, thereby encouraging a sporting culture which equates superior performance with superior hydration.
Overzealous obedience to this hydration advice has uncovered a dark underbelly to superior hydration practices: overhydration. When high school football player Walker Wilbanks died in Mississippi in August 2014 from overhydration, the doctor said that the cause of death was an “unpredictable freak occurrence.”
Two weeks prior, another high school football player from Georgia drank “two gallons of water and two gallons of Gatorade” after football practice to prevent muscle cramps and then died. Thus, over the last four years, two high school football players have died during August football practice from overhydrating – a medical condition known as exercise-associated hyponatremia.
Conversely, no football player has ever been known to die from dehydration, although seven died during this same four-year period from heatstroke, which may be related, but not always.
How much water do you really need to stay healthy?
How do I know about that overhydration kills athletes? I watched runners almost die after drinking 100 cups of water during a marathon because they were scared of becoming “dehydrated.” So, I got interested in thirst.
Turns out, the neuroendocrine thirst circuit dates back 700 million years and is found in most animals, including bugs and worms. Thirst activates the same conscious area of the brain that tells us we’re hungry or have to pee. To say we need to stay “ahead of thirst” (or die) is like saying we need to pee every hour to stay ahead of imminent bladder explosion (or die). The molecular and neural circuits that govern fluid intake (and micturition) in real-time are absolutely exquisite.
It’s remarkable to think that animals survive without water bottles and urine charts — they drink when they are thirsty, and we should too.
Too much water, too little salt
Hyponatremia is caused by drinking too much water or sports drinks, which dilutes blood salt levels below the normal range. Any sudden drop in blood salt levels, from drinking more than the body can excrete, can cause all cells in the body to swell. Brain swelling from hyponatremia can cause headaches and vomiting, while muscle cell swelling can trigger whole-body muscle cramping.
What is most frightening, however, is that these symptoms mimic those of dehydration They are often treated by medical staff with more fluids.
So, which hydration imbalance — dehydration and overhydration — is the lesser of two evils?
Dehydration is undeniably harmful to human health and performance. Wrestlers have died from trying to “make weight,” through vigorous dehydration practices. A recent meta-analysis of 33 studies verified that more than 2 percent dehydration impairs cognition. Dehydration can impair performance and increase core body temperature, as per the American College of Sports Medicine’s latest position statement. All of these statements underscore the vital importance of staying hydrated.
But I fear that many coaches ignore the finer points that support those conclusions. For example, three wrestlers who died of dehydration rapidly lost about 15 percent of body weight by withholding fluids while exercising in a hot environment in a rubber suit. Similarly, to achieve 3 percent dehydration, which impairs cognition, individuals need to withhold fluids for 24 hours. And that’s without exercise.
How much water should we drink?
These dehydration protocols do not necessarily represent “free-living” situations. When hikers die from dehydration in the desert, most if not all had become lost or had run out of fluids. Thus, thirst – or the “deep-seated desire for water” – is rarely “broken” when healthy people die from dehydration. Morbidity and mortality occur when there is no fluid available, fluids are withheld, as in lab studies, or when athletes refuse to drink for other reasons, such as “making weight.”
When do athletes and others need to drink?
So how much fluid should football players — and all other humans for that matter — drink? If you ask fluid balance experts who perform basic science research on the brain or kidney, or clinicians who specialize in fluid balance disorders, researchers who perform brain scans on dehydrated and overhydrated humans, or even worm investigators, they all agree that water balance is tightly regulated and that all land mammals need to drink when thirsty.
Drinking when you are thirsty is not “too late,” because the thirst mechanism is hardwired into the nervous system to protect against scarcity. Thirst represents the highly individualized signal which protects the balance between water and salt regardless of size, activity or ambient temperature and is encoded in most invertebrate and all vertebrate DNA. Babies are born with this innate behavioral drive.
Then, what about the need for eight glasses of water per day? There is no evidence to support this. What about peeing until our urine is clear? Dark colored urine merely reflects water conservation by the kidney, rather than water lack by the body.
What’s a football player to do?
Football players absolutely need water, but they should be warned not to overdo it.
In the modern era, where fluid is widely available, in order to stay adequately hydrated, the following must occur:
A variety of fluids needs to be freely available to football players, and
The players should be given the freedom to drink whenever they feel thirsty.
And when the players get hot, they need the opportunity to pour generous amounts of ice water over their heads instead of into their mouths to promote evaporative cooling, rather than dilute sodium levels. Better yet, they should be allowed to go inside and cool off.
We should recognize who the “true champions” may be with regards to most modern day hydration advice. According to the latest figures, bottled water sales have increased to $18.5 billion, up 8.8 percent from the previous year. This revenue does not include the vast array of purified, infused, oxygenized, sparkled, distilled, intravenous and reverse osmosis versions that compete for attention on the market.
While we all need water, drinking until our “urine is clear” is money (and water) flushed away. And with the threat of overdrinking high in motivated athletes, I ask coaches/trainers to reconsider before enforcing the urine color chart in athlete locker rooms: Is it worth the risk?
This article was originally published on The Conversation.