Medical revision: You probably don’t need to drink 8 cups of water per day (and you can eat more cheese)

January 3, 2023 • 9:15 am

Now I’m not a doctor (I just play one in academia), so I’m not going to tell you to stop drinking so much water. After all, some people need to. But the upshot of this new article from The Washington Post (click on screenshot below) is that most people don’t have to act like camels, swigging and guzzling from their fancy water bottles that they tote everywhere. They even guzzle in public!  If you drink only when you’re thirsty, most people will be fine. Read on:

I have to say that, as a curmudgeon who been this way for decades, I always feel a bit snarky when I see full-grown adults toting water bottles everywhere with them, and swigging at random. Surely much of this comes from the medical “wisdom” that you need to drink 8 cups of water (roughly 64 ounces, or half a gallon) per day. And, of course, there’s water available everywhere in America, so you don’t need your own personal bottle.

I see much of this as an infantile behavior: adults needing, like infants, to suck on a bottle full of liquid. It’s just like adult cats “kneading” as a leftover behavior from their kittenhood. (Of course, I do carry a water bottle if I’m out for the day in a foreign land (many places don’t share the American habit of having water fountains widely available), or in places where the local water isn’t safe to drink (e.g., India).

But otherwise, I just don’t like drinking water. It has no flavor, and I drink it only when I’m thirsty. Usually that’s in the morning before coffee, and then with dinner (along with wine). I seem to do fine on about 20 ounces per day, and have never been dehydrated. Even worse: the medically-inspired advice to drink lots of water has even boosted the most useless industry ever: bottled water, which is no better than tap water and has the byproduct of producing plastic refuse:

Now I know what some readers will say.  “I LIKE drinking water!” If so, more power to you, but I take that statement with the same grain of salt I do when someone tells me “I LIKE eating broccoli” or “I don’t eat desserts because I don’t like sweets.”  But this news, from last month’s Washington Post, heartened me. No longer do I—or you—have to feel like if you’re not sucking on the adult version of a baby bottle, you’re doing something wrong.

Here’s the news, and look at where that medical dictum comes from! (My bolding):

We’ve all heard the age-old advice to drink eight cups of water a day. But if you fall short, don’t worry: That advice is probably wrong anyway.

That’s according to new research, published in the journal Science, which found that for most healthy adults, drinking eight cups of water a day is completely unnecessary. The advice is misguided in part because it doesn’t take into account all the water that we get from our food and from other beverages like coffee and tea. The research found that our water needs vary from one person to next and depend on factors like your age, sex, size, physical activity levels and the climate that you live in.

The authors of the study say that for healthy adults, there is no real benefit to drinking eight cups of water a day. Nor is it dangerous: Your body will just excrete the extra water you consume in your urine.

“If you drink eight cups of water a day, you’ll be fine — you’re just going to be spending a lot more time in the bathroom,” said Herman Pontzer, a professor of evolutionary anthropology and global health at Duke University and a co-author of the study.

The advice to drink eight cups of water a day stems from a 1945 recommendation from the Food and Nutrition Board of the National Research Council, which encouraged adults to consume about 64 ounces of water daily. The recommendation referred to a person’s total daily intake of water, including from all their foods and beverages, but it was widely misinterpreted to mean that people should drink eight 8-ounce glasses of water every day.

Some experts have argued that the widely held belief was not rooted in science. One study of 883 elderly adults for example found that there was no evidence of dehydration among the 227 people in the study who routinely drank less than six glasses of water daily.

“Until we have more evidence-based documentation that fluid intake of eight glasses per day improves some aspect of an elderly person’s health,” the researchers concluded, “encouraging a fluid intake above a level that is comfortable for the individual seems to serve little useful purpose.”

Nevertheless, the advice is so widely ingrained that many companies use it to market products. You can buy 64-ounce water bottles designed to motivate you to drink the equivalent of eight cups of water daily, and water-bottle sensors that will track your water intake and remind you to “hydrate” every 30 to 40 minutes.


“We have guidelines telling people how much water to drink,” said Pontzer, who wrote a book on metabolism called “Burn.” “But the reality is that people have been kind of making it up.”

Indeed. I am comfortable with two or three medium sizes glasses a day, on top of wine, coffee, and other beverages. I estimate that I drink about 24 ounces of pure water per day—less than half the recommendation.

I wonder if any reader will be heartened by this, or will most people get defensive and say they like water (what’s to like? it’s flavorless), or that there’s nothing to lose by swilling the stuff (yes there is: hours in the bathroom). Many of my male friends (women won’t share this information) tell me that they get up several times per night to urinate.  I never have to do that, and I’m fine.

Here’s what the article recommends (my bolding again):

So how much water should you drink? The answer is simple: Drink when you’re thirsty. Prioritize water, and try to avoid sugary drinks, which can cause metabolic problems. Coffee and tea are fine as well.

Get that? (I bet you were going to inform me that coffee is a diuretic.) It seems that, all along, I’ve been doing what’s recommended. The final advice:

While the caffeine they contain can increase urination, they will still be hydrating so long as you consume less than 400 milligrams of caffeine, Rosinger said. Keep in mind that you get water from your food as well. Some water-rich foods are fruits, vegetables, beans, yogurt, brown rice, and soups.

“If you’re paying attention to your body and drinking when you feel like you need to, then you should be fine,” Pontzer said.

And here’s the Science paper, which reports that a lot of normal water intake (up to 50%) comes from food, and 85% from food and other liquids, including coffee and juice). Water generated by your metabolism constitutes about 10% of your daily water usage. Drink 8 glasses per day? Fuggedaboutit!

I have more good news too, also from the Post. Click to read:

An excerpt:

. . .when people talk about their fondness for cheese, it’s often in a guilty way, as in, “Cheese is my weakness.”

“Cheese is packed with nutrients like protein, calcium and phosphorus, and can serve a healthy purpose in the diet,” says Lisa Young, an adjunct professor of nutrition at New York University­. Research shows that even full-fat cheese ­won’t necessarily make you gain weight or give you a heart attack. It seems that cheese doesn’t raise or reduce your risk for chronic diseases, such as heart disease and Type 2 diabetes, and some studies show it might even be protective.

Don’t sue me if you stop drinking water, chow down on cheese, and then get sick. I am just the messenger here!

73 thoughts on “Medical revision: You probably don’t need to drink 8 cups of water per day (and you can eat more cheese)

  1. What I’ve observed is that people vary widely in their daily water needs. I drink much more water than my husband who outweighs me by fifty percent. He claims his minimal water needs are a genetic remnant from his Norwegian ancestors who had to survive long sea voyages with little fresh water…plausible, I guess.

    1. I remember as a kid in the early 70s heading out of the house, playing in the hot sun for several hours, then coming back in for a glass of water. It was good, but I don’t remember thinking, My god, I am drying up.

  2. I’m so pleased to read this. Thank you. I rarely drink water except to swallow a pill, and it tastes nasty too. A man of many years I drink tea and coffee and beer and wine to no ill effect. I like a lotta cheese too.

    1. You’ll also be happy to know that coffee and tea counts as water/hydration…there are no significant “dehydrating” effects from the coffee bean or tea leaves. Another silly health myth that was probably based on some study of 6 people in 1935 or something….

      1. Of course 8 cups are including all food etc. But never listen about dehidratation. And yes to avoid renal diseases. Kidney Stones, bacterian infections are eliminated by urin. And no! Only minutes in bathroom.

  3. Ditto on the water thoughts. I always thought people carrying a water bottle around with them was some odd cultural affectation. I can’t imagine anyone in modern society being so far away from a drink they needed to carry a supply of water with them. If I drank 8 glasses of water a day I’d be urinating every 30 minutes. “Drink when thirsty” has always worked for me, I figure with millions of years of evolution behind it, my body knows what it needs, even during strenuous activities.

    1. Its a pity but no. Millions of years with a selvatic diet -full of fivers, fruits, vegs- and suddenly in few years agriculture and processed meals. Drink a lot, your body probably doesent know so well.

  4. 1. “safe to drink”

    That’s what the residents of Flint, Michigan were assuming until it wasn’t. Water pipes needs anti-corrosion treatment – many are old, and expensive to replace, and are left in-place, so the “safe” anti-corrosion additives have to be put in the water. Do the pipes contain lead? It depends and we don’t know on-the-spot.

    2. My go-to for a scientific summary on water and related things :

    Dietary reference intakes for Water, Potassium, Sodium, Chloride, and Sulfate
    National Academies of Sciences, Engineering, and Medicine. 2005. Dietary Reference Intakes for Water, Potassium, Sodium, Chloride, and Sulfate. Washington, DC: The National Academies Press.

    Somewhat impenetrable, though.

    3. Water tastes better (IMHO) the less the conductance reading is.

    4. I pledge to leave only one comment on this!

    1. Addendum :

      A visit to any local home center’s plumbing aisle will turn up a number of products that interface with water. It can be amusing to count how many of these products are labelled with California Prop. 65 labels. The number of labels with lead – as in plumbous, Pb – are interesting to note, as are the expected location in a water installation the should be.

      I am careful to claim if it is in potable water, waste water, forced hot water, etc., where lead might be irrelevant to drinking water – but it is easy to verify these labels and products. Perhaps a special center has lead-free products that only professionals are allowed into, I don’t know.

      1. Your resistance held for nearly 2 hours!

        t can be amusing to count how many of these products are labelled with California Prop. 65 labels. The number of labels with lead – as in plumbous, Pb – are interesting to note,

        Does this mean that America in general (California by exception) doesn’t apply RoHS standards? Essentially, the only thing you’re allowed to manufacture with lead in is lead-acid batteries. Solder – electrical and plumbing – is lead-free (to avoid cross-over use – electrical solder in plumbing jobs). Piping is made from lead-free compositions – electrolysed copper or plastic (plastic glues being made without lead).
        I thought they were global standards. Certainly I frequently see RoHS certification (honest or forged) on a lot of cheap Chinese electronics – and that’s probably referring to the solder question again.

        1. Good question. Short answer : I don’t know (but I’ll be thinking about it now).

          The U.S. has some laws to help in that category.

          I noted where in an installation a piece might be. So wastewater might be ok with lead (I don’t know).

          I’m just astonished these things are sitting out in the open anywhere to be handled with labels saying the product can expose “you” to “lead”.

          1. I noted where in an installation a piece might be. So wastewater might be ok with lead (I don’t know).

            And the “waste” water goes downstream from the sewage processing plant in the river … and into the inlet of the next water treatment plant.
            Not your problem if you live on the coast (e.g. Aberdeen, Glasgow, London) and don’t eat much seafood. More of a problem if you live inland (where I grew up, and why I never trusted seafood) or do eat seafood. My home town fed it’s water plant from an agricultural catchment area, so cow shit was more of a concern than lead. But places like London, taking it’s water from the Thames downstream of the factorise of Oxford and Swindon … Or Glasgow whose water supply starts near the village of Leadhills (I wonder how it got that name?) then passes through Lanark or Hamilton …
            There is a classic joke that the water in London must be particularly pure because it’s been through seven sets of kidneys already … I’m sure there is an American version of that joke. Or one per State?

            The logic behind the RoHS regulations – whoever came up with them – is to simply stop adding lead to the environment. Including some big sticks for people who casually dump lead containing wastes. Which is why Dad wants me to turn the lead pipe that he (fairly casually) chucked into a corner of the cellar half a century ago, into something innocuous but useful. So, the local SCUBA club is going to acquire a lot of weights. Probably several years worth of recruits.
            (Most of my leads have a density of about 11 tonnes/m^3 : I scavenged a lot of tungsten carbide from a really tough well a long time ago – density 16+.)

          2. Of course I agree with your detailed assessment, I was only referring to local law as to what is acceptable – hedging, in a way, rather than saying I personally think there should be absolutely no lead.

            Yes, it’s happened again, I resort to “no NEW comments” – I tried “addendum” this time. Pfff.

    2. 3. Water tastes better (IMHO) the less the conductance reading is.

      We used to use de-ionised water – which we had to de-ionise directly into the shift’s use tank every 8 hours or less, through a conductivity meter – to produce chromatographic grade hydrogen for the gas analysis systems. I’d say precisely the opposite. But that’s getting up to 8-nines of purity – far above drinking water standards. Order of several ppb (footnote) contamination, or we had to put it back through a new ion-exchange column.

      “safe to drink”
      That’s what the residents of Flint, Michigan …

      That reminds me – next time I go to visit the parents, Dad wants me to “make useful” about 20 kilos of lead pipe that we took out of the house in about 1975. I think we got it all, but Dad wasn’t zealous about necessarily getting every inch of it. I think there’s a couple of through-joist joints still in place, but they may have been bypassed by subsequent plumbing work – the bathroom has been rebuilt several times since then. As an industrial chemist, Dad looked at the pipes as we took them out, noted the mm+ coating of calcium carbonates from the “hard” water, and figured the water wasn’t actually coming into contact with much lead any way – just a lot of calcium (and magnesium) carbonates.
      I infer that the water supply of Flint is “soft” not hard.
      Up here in Scotland, most of the water is soft. It varies a bit (the limestones in the Central Belt Coal Measures do harden up the water there a fait bit. So there is a remaining problem of exposed lead in water pipes in older buildings. But there are still buildings whose plumbing hasn’t been renewed in 70 or 80 years – particularly the “not user facing” bits of piping – with the distinctive “spindle-shaped” joints of “wiped” lead solder. You can see them in the service pipes in hallways between apartments. The apartment owners don’t like people trying to take a lease to ask questions like this, because it implies significant cost. They’d rather wait until there’s a fire and they can put the replacement costs onto the insurance ticket.
      OTOH, in 1920, 1930, when a lot of the housing stock had running water installed, water with a ppm(footnote) or so of lead in it was probably still an improvement on water with a ppt (footnote) or so of cholera, dysentery etc bugs. I had a friend who arrive in Aberdeen to work in the shipyard just in time to be greeted by a typhoid outbreak. Which was generally blamed on the water supply, though that was fake news.
      As my diving (and mountaineering) safety teachers would point out, you can “live for three weeks without food, three days without water, but three minutes without oxygen ; so prioritise which problem you deal with first”.

      4. I pledge to leave only one comment on this!

      See my previous comment.
      footnoteppb/ ppm/ ppt : parts per billion/ million / thousand.

  5. The 8 glasses of water per day myth was debunked years ago, but has been kept alive by a “hydration industry” that depends on this myth to keep the revenues flowing in.

    The 8 glasses myth never made sense to me, as it relies on the weird assumption that our thirst mechanism is not that well-tuned…as in even if you’re not that thirsty, you are still dehydrated!

    In fact, from an evolutionary perspective, it would make little sense for African apes such as us to need that much water or for our thirst mechanism to be so faulty. Did our ancestors, living in hot conditions and using our highly efficient cooling method of sweating, even have access to that much water a day?

    It would not surprise me to learn that homo sapiens is capable of losing fairly large quantities of fluid per day and still being fine, as long as we are able to hydrate when our thirst mechanism really kicks in.

    1. The 8 glasses of water per day myth was debunked years ago, but has been kept alive by a “hydration industry”

      That’s a significant factor, indeed.
      Working in the tropics, under the midday African sun, with a manual labour crew for most of whom English was a third or fourth language … the strategy we took wasn’t about “drink so much”. We made plenty off water available (we’d literally use a crane to lift an new tonne of bottled water to the pipe deck/ derrick area from the dry store) to the deck crews, and posted “check the colour of your pee” notices in every public (non-cabin) toilet. Much simpler.
      Oh, ghods – horrible memories of those toilets and the urgent stomach cramps from the anti-malarial drugs. [SHUDDER]

  6. My experience: Now I’m older (82) I had often difficulty with a hard stool. When I started drinking more water during the day the problems disappeared. My possible explanation: maybe we experience less thirst when growing older.
    I don’t think there’s a Nobel prize in it for me. 😉

  7. “Drink when you’re thirsty” is great advice, unless you really drink too little, at which point you don’t feel your thirst anymore. I’ve been there. I live in Germany, where I drink tap water. However, when I lived in the U.S., I used to fill gallon bottles (which I kept reusing, of course) with reverse osmosis water at the local health food store. That tastes much better and makes better tea than unpurified Minnesotan tap water, which I don’t trust. And no, purified water isn’t bad for you and doesn’t cause electrolyte deficiencies, unless you drink too much of it, of course.

    1. R.O. Water? Where you push the salt and electrolytes out of the water into the “waste” stream, concentrating any bacteria, organic toxins etc into the stream of drinking water …

      That tastes much better

      So, there definitely was something in there other than H2O (see my previous comment about parts per billion purity water).
      You’ve got to trust that health food store to consistently change those expensive filters on their water maker (that’s what we call the R.O. machines at work) and to add the right sterilizing chemicals to the water before bottling/ storing/ dispensing.
      Oh dear. A “health food store”. So no evil “chemicals”. You must have really trusted them. With your life. Well, you’ve survived. So far.

  8. I hardly listen to dietary advice, sticking to the old food pyramid. It seems like so much of it is ideological. Now apparently it’s good to be obese. Next up? Bugs.

    1. Ideological or commercial. I too was taught the Food Pyramid starting in primary school, and only recently learned that its makeup was more heavily influenced by agribusiness lobbies than by the then-available nutritional science.

  9. Meh, I did keto for nearly four years and didn’t eat sugar or carbs (pasta, rice, bread, etc). Gradually during the lockdown while working from home and on keto, my diet went from meats, eggs, and diary to primarily cheese. I imagine I’ve eaten more cheese than most on the planet. However, calories in, calories out. I gained weight on my cheese-based diet. I’m no longer on keto and switched to daily (18-hour or more) intermittent fasting, which feels a lot better. I am, however, limiting cheese for the time-being because it is so satiating–not because I see it as unhealthy. It’s better to have a wider range of foods than to be satiated so much on cheese. As for water, I drink several liters a day. When I don’t, my urine is dark. I’m not a fan of bottled still water except when traveling to places where the water isn’t safe. I do love fizzy water and have some every day. I think increased hydration is important when sick and exercising a lot. I drink a lot of water when at the gym. It’s also good for appetite suppression, especially when combined with the right balance of electrolytes.

    1. Also, I have examined the genetics of cheese intake in relation to a host of health and behavioral traits and have published on this! There is shared underlying biology between having been breastfed, higher cheese intake, longer lifespan, and more education years. I don’t think that eating more cheese directly or only causes one to live longer, but it does seem to be marking getting enough nutrition early in life. Fascinatingly, I observe the inverse for cheese intake and antisocial behavior and susceptibility to Covid early in the pandemic (prior to vaccinations): more cheese eating is protective! Well, these are genetic *correlations*. They are not necessarily causal. Again, they point to a shared underlying biology between the traits.

  10. Also as a curmudgeon, i thought the “8 glasses a day” obviously failed to consider other sources of water.

    On a more important note, Pontzer and Coyne might need to be checked for urinary tract obstructions if a little extra fluid results in their spending “a lot more time” and “hours” in the bathroom.

    But people like definite rules and no grey areas or individual variation, as in maximum heart rate is 220 minus age or “species” represents distinct categories.

  11. I actually don’t like sweets and do like broc, but I pretty much loathe water unless I’m really thirsty in which case it becomes nearly palatable. I don’t drink water during strenuous exercise either, just impatiently watch my fellow pickleball and badminton players hold up the game while they “water up”.

    1. People do perspire differently. I cycle commute with a colleague who sweats very little. Even on the hottest summer days he doesn’t bring a water bottle. On the way home I’ll have demolished nearly an entire bottle by the time we split off from one another.

  12. The only reason I’ve ever told a patient to drink that much water is if they are a kidney stone former (worse if they get the more rare cysteine stones). But I did see many patients whose main complaint was nocturia (getting up at night multiple times to urinate) who really just had polyuria from obsessively drinking too much water

    1. I don’t drink a lot of water, and when I do, it tends to be generic flavored (like Mandarin orange) seltzer from Vons. I probably average 2 330 ml. cans per day. The exception is when I’m mountain climbing. San Gorgonio in southern CA is about a 22-mile death march in one day, up and down, and I go through at least six liters when doing it.

      I AM a “kidney stone former,” my most recent a 7mm, 106 mg. specimen three weeks ago, 70% calcium oxalate monohydrate, and 30% calcium phosphate (hydroxy- and carbonate- apatite). I’ve been advised by my nephrologist to not get dehydrated, but never told to guzzle water either. What seems to work (this last one was the first in a few years) is avoiding salt and almonds and a few other things, and a generous intake of potassium citrate.

      And hectorburleeives, that “reportedly rivals childbirth” part? It depends. The pain isn’t from when it comes out; your urethra is large and flexible. Once it gets to the bladder, you’re fine. (Even the passage through the ureter isn’t THAT big a deal.) The pain is from BEFORE it makes its way down the ureter, when your kidney is trying to burst. Before I passed this one? I thought that I had a crunched lumbar disc. As soon as it passed, the back pain was gone. My first one many years ago? But for a LARGE dose of Demerol slammed into my right buttock, I would have gladly stepped in front of a speeding truck.

        1. Glad you enjoyed it! Dr. Glaucomflecken is wildly popular with doctors and nurses, so I wouldn’t be surprised if your nephrologist hasn’t already seen the video. Be sure to check out his other videos. They’re real gems.

  13. I have never been a big water drinker, and my wife always claim that I didn’t drink enough. The only time I take water with me is if I am at a meeting where I’m going to speak a lot and then I get dried out. As far as “moar” cheese, I can take it or leave it by my wife eats a lot of cheese.

  14. “They even guzzle in public! ”

    Is that considered to be some kind of indecency in the USA to drink water publicly? I do it all the time and it never crossed my mind that anybody would see it as weird, but I have never been in that part of the world.

  15. I live south of the rust belt and just a little north of the true Bible belt but smack dab in the middle of what I’m told is the kidney stone belt, a cinching up that I want no part of. Whether or not any science supports it, I abide by the advice to drink water frequently to avoid something that reportedly rivals childbirth for pain. But I don’t tote a stupid bottle around all day long.

  16. “Research shows that even full-fat cheese ­won’t necessarily make you gain weight or give you a heart attack. It seems that cheese doesn’t raise or reduce your risk for chronic diseases, such as heart disease and Type 2 diabetes, and some studies show it might even be protective.”

    I believe that the exact same thing can be said for meat consumption. The scandal here, and personally I believe there is one, is just who is making dietary recommendations (their independence from industry), what is the robustness of the data they are using, and what data are they ignoring.

    There is a definite bias against meat consumption by dieticians nowadays that is pushing more highly-processed foods on the public under the guise of “plant-based diets”. There is a new set of global dietary recommendations being pushed right now (EAT-Lancet) that says that a bowl of Captain Crunch cereal is healthier for you than an egg. Meanwhile, physicians who are promoting low-carb diets are seeing certain chronic problems in their patients – including Type 2 diabetes – being abated or disappearing altogether.

  17. A cartoon I saw many years ago is lodged irreversibly in my brain: a thirst-addled man is shown crawling on his hands and knees through a desert, crying “seltzer, seltzer”. I have
    long taken this image to heart, so that my daily water consumption is mostly carbonated. On the business side, I am planning an enterprise that will sell to the fad-hungry US public little portable containers of bottled air.

    1. You can apparently already buy jars or cans of Canadian, Scottish, Swiss, and other regional air on eBay, though I’ve never looked. Apparently it’s allowed some purveyors to quit their day jobs and make a good deal of money. So, there is a market, it’s all in how you sell it! I recommend also targeting the air-pollution-plagued regions of China, apparently they are big purchasers of the canned air.

      1. Mel Brooks beat us to the joke by a few decades with President Scroob huffing canned air from Druidia in Spaceballs. What he didn’t predict is that people would pay for jars of social media influencers’ farts. What a sick, sad world we live in.

      2. buy jars or cans of Canadian, Scottish, Swiss, and other regional air on eBay

        I don’t know about the others, but Scotland’s canning plant is part of the Grangemouth oil refinery site, next to the sewage farm. We add that certain je ne sais quoi.
        Someone was taking their Python worship to a truly sublime level when they started that industry.
        “Wheresoever three or more are gathered together, they shall perform the Parrot Sketch!”

  18. “I LIKE drinking water!” If so, more power to you, but I take that statement with the same grain of salt I do when someone tells me “I LIKE eating broccoli” or “I don’t eat desserts because I don’t like sweets.”

    I do like drinking water when I’m thirsty. It’s not the taste, it’s the pleasure of slaking my thirst. That said, I do not drink a lot of water during the course of a day. The taste of other liquids seems to get in the way of thirst slaking.

    I do drink a lot of coffee and tea and sometimes alcohol and I admit that a cold beer tastes wonderful if I am thirsty, even if it is less effective objectively.

    I do love broccoli and I pretend I am not a fan of sweet desserts, although, hypocritically, when it comes to the crunch of picking something off the dessert menu in heathen cultures where cheese is not a separate course (e.g. mine), I will almost always pick the tiramisu over the cheese.

  19. I never believed the water nonsense. Like you, I’ve noticed that people drinking from their water bottles look like babies. That might be simple bias on my part.

    I would also add that the water fetish probably stems in part from the widely-held nonsense that people need to “cleanse” or “detoxify” all the terrible chemicals that accumulate to harmful levels in the body. (Nonsense, of course.) Drinking lots of water supposedly removes these “toxins.” If you watch carefully, you’ll notice that the “toxins” foolishness crops up often, particularly when discussing food supplements.

  20. And yet:

    Now, new research shows adults who stay well-hydrated appear to be healthier, enjoy a lower risk of developing chronic diseases and may live longer overall compared with their less-hydrated peers.

    That’s according to an NIH study published in eBioMedicine. Data from more than 11,000 participants collected over 25 years revealed higher serum sodium levels — which rise when fluid intake decreases — were associated with a 39 percent increased likelihood of developing chronic conditions like heart failure, stroke and dementia, compared with adults who had levels in the medium range.

    Adults with higher levels were also 21 percent more likely to die at a younger age.

    “The results suggest that proper hydration may slow down aging and prolong a disease-free life,” said study author Natalia Dmitrieva in a release. Dmitrieva is a researcher in the Laboratory of Cardiovascular Regenerative Medicine at the National Heart, Lung, and Blood Institute.,Good%20hydration%20linked%20with%20lower%20risk%20of%20chronic%20disease%2C%20increased,a%20disease%2Dfree%20life.%E2%80%9D

    1. Thanks for that, Lysander. The original study is here:

      It’s a longitudinal observational study of people screened as being healthier than a random sample. They were trying to avoid confounding with people who were already sick. The authors measured serum sodium levels twice, three years apart in middle age and followed the subjects for 25 years. Impressive work in follow-up.

      The subjects, about a quarter, who started out with sodium levels at the high end of the normal range, indeed had a 21 % higher risk of dying during the study period. (But as life insurance companies know, the risk of a healthy 50-year-old dying before 75 is quite low, and these subjects were screened to be healthy even more vigorously than insurance companies do.) The impact on “physiologic age” and the development of chronic diseases is more complicated than I can do justice to here but goes in the same direction as deaths.

      Not highlighted in the The Hill report, though, is that those (about 10%) with serum sodium levels at the low end of the normal range had twice the risk of dying, compared to those at the sweet spot of 140-142 mmol/L. They do some hand-waving to explain this away.

      My main criticism is that we don’t know that the sodium level in any individual participant was in fact related to how much water s/he drank. Most of us have a “set point” around which the sodium concentration varies very little, regardless of how much we drink. Under normal good health the kidneys retain or shed water, and our brains stimulate thirst or refusal of water, to keep us at that set point. The authors don’t demonstrate that anyone can, through volitional effort (drinking) maintain a serum sodium that’s different from the baseline set point for any long period of time (like 25 years.) To be fair, they do cite small population surveys (not experiments) that show a correlation between sodium levels and water consumption.

      It is likely that “sweet spot” levels of sodium are merely markers of “good health” (whatever that means). The authors are quick to ascribe high-normal levels to inadequate hydration but just as quick to ascribe low-normal levels to “subclinical diseases of water and electrolyte regulation.” How do we know that the doubled death rate in this group is not due to over-hydration?

      The other possibility is that old determinant of health: socio-economic status. They collected this information but didn’t include it in their analysis. If serum sodium status is indeed determined by how much you drink, perhaps it is well-off educated lean white non-smoking health-conscious liberals — the ones who will live forever — who picked up the fad of 8 glasses of water a day and can incorporate it into their daily work routine. They probably eat kale and floss regularly, too.

      I’m still going with drinking water only to keep from getting stiff in the joints. Trouble is, a lot of the joints don’t serve water.

  21. I am one of those odd people who are thirsty for cold water throughout the day. I drink water numerous time during the day and sleep with a water bottle on my nightstand. I have always been this way and have been tested for diabetes from an early age because of my water consumption. My brother is the complete opposite and seems to rarely drink water. I’ve always felt that there is a great variance on the need for water consumption between individuals.

  22. I can’t wait to show this to my Mom who basically stopped drinking water after her last pregnancy in 1969. I guess her doctors recommended a lot of water during pregnancy and she got sick of it after seven. She drinks mostly coffee, tea, and wine with the occasional tomato juice. She’ll be 91 next week!

  23. I try and have a litre bottle of fruit flavoured water to hand in the house which I usually drink during the day. I have a cup of tea when I get up, and maybe two or three cups of coffee during the day. The only point I would make is that if you do strenuous exercise during the day, for me running or gym, then that can incur substantial additional liquid requirements. Even when it’s cold I lose a litre of body fluid in an hour, and over two litres if it’s especially hot.

  24. This is not the first time the drink-8-glasses-per-day received wisdom has been debunked. Good to see it is in a MSM article. Some even claimed this must be in addition to coffee, tea, fruit and other fluids we get eating and drinking. Never passed the common-sense test. I enjoy drinking tea all day long, so I am getting lots of water as it happens. Glad to hear cheese is not bad for you as I love cheese. Also, broccoli is my hands-down favorite vegetable. I think it actually tastes different to different people. It does not taste bitter to me, but many vegetables do.

  25. I am not a scientist but i believe that eating meat increases thirst because it is a
    dense protein that requires more energy to be metabolized, and this creates body heat and a desire for water. Of course diabetics need to drink sufficient water, especially if they eat carbs, which increase thirst (so does fruit juice). As for cheese, it is probably one of the most nutritious foods available and for eons provided protein, vitamins and minerals when meat was unavailable. Its bacteria and enzymes not only make it taste great but perhaps provide some probiotic protection???Anyway, it was invented as a way of storing milk, as was yogurt. Raw milk cheese of course tastes much much better than pasteurized, and generally speaking artisanal raw milk cheese is quite safe, much safer than industrial cheese because it doesnt go through the industrial process that requires more handling, more transport and more chance of contamination. The US government paranoia about imported raw milk cheeses is way overblown; those that are contaminated are almost never artisanal cheeses produced by a single cheesemaker on his own farm but commercialized industrialized cheeses prepackaged and distributed widely to mass markets. These are often lower in acid than the raw milk cheeses and thus less resistant to harmful bacteria. You can get a few raw milk cheeses in this country (though not the soft ones like Camembert and Reblochon), or order from, a French export company. Prices per pound are very reasonable but shipping costs high! Long live French raw milk cheeses! They make life worth living. My favorites besides Camembert: Pont l’Evêque, Maroilles, Raclette, Livarot, Comte, Morbier, Abbaye de Citeaux, Fougere…all raw milk, plus pasteurized Stilton, best of the blues). Raw milk Brie a good substitute if you cant get raw milk Camembert).

  26. Jerry’s distaste for drinking water reminds of a comment from a character in an old favorite story. When offered water to drink he replies, “I’m thirsty, not dirty. Wine, if you please.”

    I don’t drink large amounts of water daily, don’t carry a water bottle unless I’m going out hiking, kayaking or similar long term strenuous outdoor activity, but water is about the only thing I do drink. I don’t normally drink milk, juices or softdrinks, just water. Well, one 300 mg caffeine energy drink per day. And alcohol for pleasure. I don’t drink water to try and be healthy or anything like that, I just prefer it. Milk makes your mouth taste and smell like a charnel house within a few minutes of drinking it and sweetened drinks like fruit juice and softdrinks I find way to sweet. They tend to make me really thirsty.

    It amazes me how big of an increase in water intake can be necessary to sustain you when you engage in long term hard activity in hot conditions, and even worse high humidity. I recall one day motorcycle racing (track day, not real racing) where it was very hot, about 103 F (40 C), and humid. I was riding 15 minute sessions with about 30 minutes between from about 8 AM to 5 PM (a break for lunch). Between every session I was drinking 1 20 oz (590 ml) bottle of water plus 1 12 oz (360 ml) bottle of Gatorade, and it wasn’t enough. The last few sessions I was panting like a dog through every turn and by the end of the day I had the crushing headache and general sense that you might drop dead that you only get when you are dehydrated and flirting with heat exhaustion.

  27. I know our host is sceptical about the existence of such people, but I’m a self-confessed broccoholic (I can tolerate Brussels sprouts, too, but I’m not a fanatic like WEIT reader Dom who had pizza with a sprouts topping for his Christmas Day lunch when we had to cancel our invitation to him at short notice to attend my mother-in-law’s funeral in Spain) and don’t eat desserts (I did when younger, but for some reason no longer have a sweet tooth). I’m not a great drinker of tap water (sparkling water is fine, though) – and I probably eat too much cheese, especially at this time of year.

  28. My favourite Laurel and Hardy film is Them Thar Hills in which the boys are implored by their doctor to get fresh air in the country and drink “water – and plenty of it!” as a health cure. Unbeknownst to them, the well at their rural retreat has just had whisky tipped down it by some bootleggers escaping from a police raid. It tastes better than expected and they follow the doctor’s orders, with hilarious results…!

  29. I absolutely LOVE water, and feel a deep visceral pleasure when imbibing, which I do at the rate of at least, I dunno, 8 to 12 litres per day, and far more when physically active or in nature with an endless supply at hand. That’s not including limeade, tea, coffee, et cetera (I loathe wine but will occasionally sample a fine whiskey). I once failed a urine test because it was basically indistinguishable from H2O (I returned 3 days later having breakfasted on coffee, artichokes, asparagus, and brewer’s yeast, and passed handily). It never occurred to me that anyone was judging me for “guzzling in public”. Who cares?

    Then again, I like broccoli, eschew desserts, and the Beatles don’t make my top 300, so… vive la difference, I spose.

  30. Excellent advice on water, Jerry. And you are right also that coffee is not a net diuretic. The caffeine does increase blood flow to the kidneys which, given the water in the coffee, produces an appropriate mild increase in urine production. Just what you’d want. (Funny how the naturopaths tout various nostrums and potions as “natural diuretics” but then turn around and condemn coffee for supposedly doing the same thing!)

    I like to say that our most important organ is the kidney because it allowed us to survive as macroscopic land animals, maintaining the salt and water content of our bodies within precise limits outside of which we get seriously ill. And it does it all by relying on nothing more than the thirst mechanism, a taste for salt in food, and the common sense to stay out of the noon-day sun in hot lands. My off-the-cuff hypothesis is that whales could only have evolved from terrestrial mammals and not from fresh-water aquatic precursors. (And it might even be true:,when%20only%20saltwater%20is%20available.)

    They needed the dry-land kidney as a foundation to cope with drinking sea water, or not drinking much water in the first place. Our kidneys can de-salinate physiologic saline (0.9%) under the right kind of stress but not seawater (3%). (The kidneys do many other seriously clever things, too.)

    While it is true that dehydration during prolonged exercise can be insidious — smart as it is, the kidney has priorities — too much water can be bad for you. Drinking before you’re thirsty is time-honoured endurance exercise advice but works better when you don’t have unlimited access to water along the course and have to husband what you can carry on your bicycle. Healthy people just pee out the excess (annoying at night for older guys like me) but marathon runners, water-drinking stunt contestants, inveterate beer drinkers, surgical patients, and schizophrenics have died from water intoxication. It is a medical emergency and difficult to treat.

  31. I think the problem is you can’t tell people to do anything when they feel like they should. People need rules, man, someone laying down the law so they don’t have to think about it! My sister is one of those crazy people that sucks on a water bottle all day long. Drives me crazy. But all that is neither here nor there – it was just a coincidence that just before I read your comments on water drinking (hear hear!, or is it here here?) I read this article:
    Headline – Good hydration linked with lower risk of chronic disease, increased longevity: study

    1. Sorry but your first sentence is wrong. You can tell people to do things that they don’t want to do, like stopping drinking. Now you could say, “Well, they must have wanted to because they did it,” but then your claim becomes a tautology.

  32. I appear t be in the minority here, but I rarely drink anything except water; I prefer water. I drink an average of about 2/3 of a gallon of it per day. I don’t force myself. It just turns out that way. I like it at room temperature, not very cold.

    I never liked the fuss and effort and expense of drinking stuff other than water. Just not worth the trouble. Perhaps this comes from my having spent very long continuous periods living in wilderness with no easy access to anything else.

    1. I’m very much with you there; when in the high Sierra Nevada, for example, I go for weeks drinking nothing but enormous quantities of that cold, clear mountain elixir — well, sometimes I make soup with it or, after the manner of John Muir, tea. I wasn’t always this way; one reason I no longer engage in big-wall climbing or extended desert sojourns is, I miss the water!

      The opprobrium towards us water-guzzlers is a puzzler. Why does anyone care?

  33. I’m delighted to see that the WEIT community is all across the spectrum as usual!

    I like water when I’m thirsty. I much prefer beer or wine when I feel the need to swallow a liquid with some taste to it (and for some reason that need comes upon me quite often).

    My dear wife drinks much more water than I do. In fact, she takes a bottle out with her on even the shortest walks, and feels uncomfortable if she hasn’t got one to hand. I don’t usually bother for a walk under 10 miles or so (unless it’s very hot).

    I still find myself having to get up for a slash in the small hours, most nights. Twice, if I’m unlucky.

    1. PS: I love cheese. I’m glad to hear it isn’t unhealthy. Not that it would make much difference to my intake if it was! Among the few things to cheer about in the UK today is the astonishing variety of cheeses available. I can think of a dozen distinctive ones that are made within 15 miles of where I live. Add that to the number of breweries in the UK (more than at any time in recorded history, apparently), and it seems we’re getting something right, at least!

  34. an elderly doctor here in Japan advised me to drink a glass of water before going to sleep and again after getting up to help prevent blood clots

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