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Does Drinking Water Prevent Dehydration?

by Steven Novella, Nov 21 2011

Umm….Yes. Yes it does.

This is one of those stories that immediately makes me think that there must be a deeper issue that the press is missing. Recently the European Food Safety Authority was asked to evaluate and approve the following statement:

“Regular consumption of significant amounts of water can reduce the risk of development of dehydration and of concomitant decrease of performance.”

After three years of investigation the EFSA concluded:

The Panel considers that the proposed claim does not comply with the requirements for a disease risk reduction claim pursuant to Article 14 of Regulation (EC) No 1924/2006

This decision has been immediately and widely criticized as absurd – the EFSA is saying that water does not prevent dehydration. It’s surreal. It right out of Brazil, a dark comedic dystopian totalitarian nightmare. Or perhaps it’s just abject stupidity.

I have a hard time accepting that interpretation at face value. I’m not any kind of legal expert, but it is my understanding from my involvement with legal cases that they can be decided on two grounds – the merits of the case, and the technical legal aspects of the case. For example, a court can find a defendant not guilty because the facts imply that they are actually not guilty of the crime committed, or because of some legal technicality.

Scientists sometimes face these considerations when pseudoscience is confronted in the courtroom. For example with the Dover intelligent design trial – that evolution is correct science and ID pure pseudoscience is a slam dunk. But defenders of science were concerned that the Kitzmiller vs Dover case may have been decided on some technical legal grounds (about interpretation of the law, for example) rather than the scientific merits.

So my first reaction to the EFSA ruling is that it must be the result of some technicality – the people filing the request used the magenta form instead of the goldenrod, or there was some problem with the wording. I can see numerous problems with the proposed wording – it does not identify a target population, it does not define what “significant” amounts of water are, and the bit about performance seems deliberately vague, as if they will try to use approval of this wording in order to slip in some dubious claim about athletic performance from drinking a particular brand of bottled water.

Or perhaps it is something even more legally obscure, such as the lack of standing or applicability of the law. There must be something.

I tracked down the actual decision, here is the abstract:

Following an application from Prof. Dr. Moritz Hagenmeyer and Prof. Dr. Andreas Hahn, submitted pursuant to Article 14 of Regulation (EC) No 1924/2006 via the Competent Authority of Germany, the Panel on Dietetic Products, Nutrition and Allergies was asked to deliver an opinion on the scientific substantiation of a health claim related to water and reduced risk of development of dehydration and of concomitant decrease of performance. The scope of the application was proposed to fall under a health claim referring to disease risk reduction. The food, water, which is the subject of the health claim, is sufficiently characterised. The claimed effect is “regular consumption of significant amounts of water can reduce the risk of development of dehydration and of concomitant decrease of performance”. The target population is assumed to be the general population. The Regulation (EC) No 1924/2006 defines reduction of disease risk claims as claims which state that the consumption of a food “significantly reduces a risk factor in the development of a human disease”. Thus, for reduction of disease risk claims, the beneficial physiological effect results from the reduction of a risk factor for the development of a human disease. The Panel notes that dehydration was identified as the disease by the applicant. Dehydration is a condition of body water depletion. The Panel notes that the proposed risk factors, “water loss in tissues” or “reduced water content in tissues”, are measures of water depletion and thus are measures of the disease. The Panel considers that the proposed claim does not comply with the requirements for a disease risk reduction claim pursuant to Article 14 of Regulation (EC) No 1924/2006

That didn’t help. They did not identify the reason that the proposed claim does not comply with regulations. That’s what I want to know – what is the reason. I read through the entire decision, and they never go into more detail. The paper simply restates information present in the abstract in different formatting and separated out into different sections, but there is no additional information. No reason is ever given.

A Telegraph article does give the only justification for the decision I can find:

Prof Brian Ratcliffe, spokesman for the Nutrition Society, said dehydration was usually caused by a clinical condition and that one could remain adequately hydrated without drinking water. He said: “The EU is saying that this does not reduce the risk of dehydration and that is correct. “This claim is trying to imply that there is something special about bottled water which is not a reasonable claim.”

If this is the reason then it is not some legal technical ruling. They actually think the claim is misleading. Assuming Professor Ratcliffe’s justification accurately describes the EFSA’s thinking, the decision is absurd, or at least misleading. Dehydration is not usually caused by a clinical condition. It’s usually (in the assumed general population) caused by not drinking enough fluids, most often due to physical activity or hot and/or dry environments. I have become dehydrated many times in my life, always as a consequence of one of the above situations (and one time because I was at high altitude). In every situation drinking water would have done the trick (and eventually treated the dehydration).

It seems what they are saying is that dehydration, when it is a “disease”, is cause by a clinical condition, and drinking water may not work. For example, if someone has terrible diarrhea and is losing significant amounts of water, drinking water will not do the trick. People can die of dysentery even when they drink a lot of water, because they are secreting water through their bowels. You need intravenous hydration to treat severe dysentery, and you need to treat the underlying condition (or at least give IV hydration until it runs its course).

So maybe – maybe – the EFSA decision is the result of the fact that they did not want to allow a blanket statement that could be applied to conditions where the claim is not true, like dysentery. I don’t know, because they did not explain their decision at all in the actual document. They therefore opened themselves up to legitimate ridicule.

My fear is that this sensational event will create a public backlash against regulatory agencies reviewing health claims by product manufacturers. This is a dramatic and emotional case that can have undue influence on what should be a thoughtful and nuanced discussion about the proper role of regulation in health claims. I suspect the anti-regulation crowd will jump all over it.

34 Responses to “Does Drinking Water Prevent Dehydration?”

  1. anon says:

    Hydration absolutely does not “equate” to intake of water, despite the magical mystery powers of “common sense”. There are in fact three types of dehydration: Hypertonic, which is the only kind you’ve ever heard of; hypotonic, which is a loss not of water but of electrolytes; and isotonic, which is a loss of both water and electrolytes. A hypotonic or isotonic patient could be given litres of bottled water without recovering, since they also need electrolytes (notably sodium).

  2. Max says:

    Here’s Regulation (EC) No 1924/2006

    Article 14 Paragraph 2

    “In addition to the general requirements laid down in this Regulation and the specific requirements of paragraph 1, for
    reduction of disease risk claims the labelling or, if no such labelling exists, the presentation or advertising shall also bear a statement indicating that the disease to which the claim is referring has multiple risk factors and that altering one of these risk factors may or may not have a beneficial effect. (emphasis added)

    Maybe the claim didn’t comply with that.

  3. Jesse says:

    “I suspect the anti-regulation crowd will jump all over it.”

    And why shouldn’t we? It’s a farce and indicative of the busybody mentality that dominates agencies that believe they’re more important than they actually are.

    • Nicholas says:

      You shouldn’t because it isn’t a farce, isn’t indicative of the busybody mentality, which doesn’t dominate agencies, which don’t believe they’re more important than they are. That’s why.

  4. Chris Howard says:

    I found myself torn between laughter, and tears. This has made me thirsty. Not to worry, I’ll just drink some… oh, crap!

  5. jesse – I agree that anti-regulation advocates have a point. Perhaps this is an example of what happens when you try to regulate basic things through top-down committees and obsessive legalese.

    My concern is that they will use this example to argue that we would be better off without any health care regulation. (as opposed to the “thoughtful and nuanced” approach I would advocate)

    • Wesley Goodford says:

      No they don’t. The bottled water companies wanted to put a dubious medical claim on their bottles, and when they got caught because contrary to their expectations it was investigated by actual scientists, they decided to run to the press for sympathy, knowing that our prized yellow journalism doesn’t let facts get in the way of writing a sensationalist story.
      But in actual fact the claim is shaky on multiple grounds. For starters, normally people tend to drink enough by themselves; people with lasting dehydration tend to have underlying physiological problems. (This is especially true in the generally mild climate of Europe, and people are already adequately informed about dehydration prevention by the government.) And there is a risk to replenishing water without replenishing electrolytes. And there is the issue that the bottled water companies intended to present their statement in such a way that it would have looked like drinking bottled water would be better than drinking whatever the customer would have been drinking otherwise (tap water, fruit juice, lemonade, ginger ale, …).
      This makes it clear that the statement would be against EU regulations, and if it hadn’t been that the regulations would need to be changed.
      So the next time you don’t understand something, keep your silence until you do. Or ask the why question instead of trotting out your uninformed opinion. Your article makes you sound like a libertarian concern troll, which I know you are not, so reflect on it.

    • Wesley,

      You’re making a lot of assumptions in your comment. I went into this with an open approach – I had no idea what was really behind the request or the decision and was just trying to figure it out.

      I could not find any info that this bottled water companies were behind the request. There is a suggestion that the request was more intended to test the regulatory process.

      Further, the decision gave no indication that abuse by industry was a concern or the reason for their decision. If you have a reference that clarifies this, please provide it.

      Finally, I don’t know how you conclude that my article sounds libertarian. At the end I make my support for proper regulation explicit and express my concern that this incident will be abused by anti-regulation activists.

      • Wesley Goodford says:

        >There is a suggestion that the request was more intended to test the regulatory process.
        Ostensibly, perhaps. But Andreas Hahn and Moritz Hagenmeyer are food advertising consultants with a known distaste for the EFSA, presumably because it makes their lives harder. Given the outrageous things Nestlé, Bar le Duc and their ilk routinely advertise with, this case didn’t fall out of a clear sky. Given the socio-economic context, the connection is pretty blatant.
        >the decision gave no indication that abuse by industry was a concern
        The regulations are there (among other things) to prevent industry abuse, but the EFSA has to follow the regulations. It isn’t allowed to judge on industry abuse directly, and for good reason.
        >express my concern
        I said and I repeat it in full that the article sounds like a libertarian concern troll. Note that last two words and look them up if necessary.
        In any case the concern is completely unjustified. This whole thing only became a story courtesy of the Telegraph. The papers will always bitch about some the imagined fascist ghost of some European rule or other, and if they can’t they just make stuff up. Look for yourself, the Telegraph article even repeated the bendy banana baloney.

    • Heath says:

      I think the motivation for the application needs to be taken into consideration. It’s obviously intended for marketing purposes and in that way while the statement is true, it’s potentially misleading to consumers. The concern that the marketers of the bottled water may imply that the product is somehow special is a valid one.

      Perhaps that’s a role for a consumer body as opposed to a health organisation, but it seems a bit like talking about bad breath as if it were a disease and suggesting the treatment is mouthwash or that hunger were a disease and the treatment is a Mars Bar.

      My question would be, is drinking water to prevent dehydration really a disease claim distinct from simply being a statement of fact? Because statements of fact are different from a disease claim, disease claims carry an implied endorsement from an authority.

  6. tudza says:

    Why is it necessary for a bottled water company to make health benefit claims at all?

    “Got water?”

    “Water, it does a body good.”

    “Water, the incredible drinkable fluid.”

    • Max says:

      They can increase sales by convincing people to drink half a gallon of water per day to avoid dehydration.

  7. MadScientist says:

    I have no idea what “disease risk factors” are being looked at so I won’t comment on the panel’s summary. As far as drinking water goes, I think the most useful thing is to tech people to spot early signs of dehydration and to drink an appropriate amount of water. Too much is no good either. I’ve had a few days where I’ve had enough to drink and yet I still felt terribly thirsty; on a few such days I’d drank so much that I felt both bloated and thirsty. Far more frequently I would be obviously dehydrated and yet have no sign of thirst.

  8. dcp says:

    “The bottled water companies wanted to put a dubious medical claim on their bottles”

    No they didn’t. This was a test case by two professors intending to show how ridiculous the regulation is.

    They succeeded admirably.

  9. The Midwesterner says:

    I really like reading your blog and look forward to it every Monday morning, but please, please, please stop making references to courts, legal procedures, etc. You clearly know nothing about them and your references herein are totally far off the mark in any situation, but particularly since I can’t see that the entity that is the subject of this entry is anything like a court of law.

    • The only analogy I was drawing was that the decision can be based on either the science or the technical aspects of the regulation. If this is a bad analogy to a legal decision, please let me know why. Otherwise your comment is not very useful.

      • The Midwesterner says:

        “For example, a court can find a defendant not guilty because the facts imply that they are actually not guilty of the crime committed, or because of some legal technicality.” This is a reference to a court of law which is not correct. The court system, through juries or a trial before a judge alone, finds defendants not guilty because the prosecuting authority has not proved their case beyond a reasonable doubt. Cases can be dismissed by judges because of “technicalities” which are violations of a persons rights under the constitution and the case law that flows therefrom. When this happens, there is no determination of guilt or non-guilt, only that the case can’t proceed because of the violation. This doesn’t happen very often. In most cases, even if a violation is found, it only applies to the evidence that results from the violation (the fruit of the poisonous tree). For example, a confession obtained without giving a Miranda warning to an in-custody person may be thrown out but if other evidence exists, the case can proceed to trial with that other evidence. All parties clearly understand why such rulings are made. Unfortunately, the word “technicality” in the context of criminal cases is usually used in a very negative way throughout our mass media – television, movies – as well as by politicians who understand (I hope) that most of those technicalities are actually rights guaranteed by the constitution but also know the average person does not so they can get away with saying it. From reading your entry, what I take away from it is that you are saying that you can’t tell if the decision was made because they don’t feel the premise was supported by science or if it was because whatever was originally submitted didn’t meet the technical requirements of the EFSA. My point is that neither of those things relates to how courts of law operate. However, I agree with you that the opinion is seriously wanting.

      • That is basically what I was trying to say, just not putting it correctly, so thanks for the clarification.

        Perhaps guilty vs not-guilty was not a good context. I think the Dover case was probably a better example, where a judge (not jury) decides a case for the plaintiff or defendant and generally can be on the merits of the case or on the technicalities of the relevant law.

  10. Glen says:

    They must have been referencing the freeze-dried water. You gotta add water to that for it to work…

  11. Miguel says:

    That evil dihydrogen monoxide should be banned at last.

  12. John Ellis says:

    If the claim were allowed, it would give Homeopathy a foot in the door as the first disease that it can be proven to cure. If you take enough of it – and the more diluted, the stronger. Oh what a slippery slope!

    • Wrong says:

      I don’t see how. Claiming that water cures dehydration says nothing about homeopathy. Of course, your comment on the slippery slope seems to indicate that you realise how stupid and fallacious your statement is, so I guess I’ll leave it.

      • John Ellis says:

        While the wet slippery slope was intended for contextual humor, my claim was serious. Homeopathy has never ever been shown to treat or cure ANY condition or disease except for a fat wallet. It’s just water. If Water is ruled to treat or cure a disease, then Homeopathy, being water, treats or cures that disease. It’s a foot in the door that can be spun wildly by homeopathic proponents to show that “sceptics of homeopathy” as they call us are wrong. Not that they would, or that it would make sense, but I AM talking about homeopathy, so sense, logic, and reality are not relevant.

        / Or did I simply miss the irony of your name?

  13. Scott Hamilton says:

    Putting aside whether or not a regulation like this is needed, isn’t it a little silly for any bottled water seller to be using dehydration as a selling point? If you’re actually dehydrated to the point where it’s causing you problems do you have time to buy a bottle of anything? Wouldn’t a water fountain or a puddle of rain water work as well, be cheaper, and (most importantly) be quicker?

    Put it another way: If Hostess were to start selling boxes of Twinkies with a big sticker on them that said, “Cures Starvation!”, would that be okay? It’s completely true, right? Howabout “Cures Malnutrition!”? Still 100% true. Some nutrition is better than none, even a Twinkie. I guess what would worry me is that even the suggestion of curing some condition like that will affect a lot of people in an adverse way. I sometimes wonder if humans aren’t hypochondriacs at heart.

    In the US, I suppose, we don’t legislate against advertising like that, judging from all the products you can buy that treat halitosis. And that may well be the best approach. But I do worry about how easily people will jump to thinking that some new product does someething REALLY important, just because there’s a scientific term attached to the marketing.

    • oldebabe says:

      Ha-ha-ha-ha…. `cures starvation’ indeed. You think you’re kidding? (Well, you probably are). Never mind the negatives, someone will find that a positive rationale. People ARE funny animals…

  14. Dan Ciora says:

    Perhaps the justification for precluding the claim that bottle water prevents dehydration is that any and all water prevents dehydration.

    The claim that bottle wetter prevents dehydration is misleading for that reason.

  15. Miguel Picanco says:

    It took me until the end to really understand the friction behind your tone in the piece..

    I really wish you would have sooner played up your root concerns about them (media?) abusing this flimsy decision to hijack government regulatory systems in general.

  16. Larry says:

    If you’re going to make a blanket health claim then I have no problem with the regulators requiring you to get it right. Simplest solutions is to have the bottled water companies to change their claim to:

    “Will cure Hypertonic Dehydration providing you are not suffering from sever dysentery.” Providing they include the disclaimer: “May cause hypotonic Dehydration if you drink more then 1 gal per day.”

  17. cfm says:

    Firstly, don’t believe that you get anything LIKE a full picture of anything from our newspapers. They have become sketchy in the extreme, and probably omitted the most important bit of what was said by Prof Ratcliffe. Think they could miss the most important bit? I read a whole report on the faster-than-light neutrinos in the Independent this week that referred to them throughout as neutrons. My 14 year old knows that’s hilariously wrong. So they can miss a LOT.

    The burden of proof in these regs is that a claim is null unless proven true, rather than assumed true until disproven, so you have to positively prove a claim to get it on the packaging. They didn’t have any proper trial proof that you were going to feel better, be healthier, perform your job better, whatever, after drinking this bottle than after not drinking this bottle – and this is the critical bit – on an average day with an average European diet. Fair enough. So you can’t sell a bottle with a claim implying it’s going to be universally great for the population unless you can prove that at least MOST people will actually derive some benefit from it. On an average day in Europe, one of those bottles of water in addition to what they normally eat and drink would make not a jot of difference to almost all of the population. We just don’t have a big dehydration problem, if oyu listen to the properly qualified scientists and doctors, no matter what personal trainers and underqualified health gurus tell you.

    And isn’t it a good idea to say you can’t make a statement to sell a product unless it’s true? We tend not to encourage lying – and claiming X is the case when you have no real idea IS lying. The expensive “friendly bacteria” yogurty drinks have had to drop their health claims, I think because they never proved their bacteria even make it through your stomach acids alive, never mind what they might get up to after that. But the cholesterol-reducing spreads are still allowed to state their claim, because it is solid. Something was allowed on cranberry juice, something else not, I can’t recall: the judgements so far have been pretty considered and sensible.

    And while we would feel righlty nannied if they tried to stop the water being sold (taxing it like booze might be a nice money raiser, though), nobody but the industry really cares about losing a bit of advertising puffery. Few people have yet noticed the bacteria claims disappearing, if you ask them. This kerfuffle over this really is just the Telegraph chasing sales. Oh, and probably the Daily Mail, who may have told us recently that water cures cancer. Or causes it. Or both, they are kind of fickle like that. Check out the Daily Mail on cancer. That’s a long running comedy show in its own right.

  18. Skeptvet says:

    As far as the technical legalese, the way I read the abstract is that the law states a risk reduction health claim is a claim that the product, “significantly reduces a risk factor in the development of a human disease.” The product must reduce a risk factor for development of a disease. However, the application claim was that the product reduces “water loss in tissues” or “reduced water content in tissues.” These are not “risk factors” for dehydration, they are the definition of dehydration (or as the abstract puts it, they are “measures of water depletion and thus are measures of the disease”). So the product is not claiming to reduce a risk factor for development of a disease but claiming to reduce the disease itself, which is not an allowable claim. It would be like saying antibiotics reduce the risk of developing an infection by curing the infection.

    As others have pointed out, of course, the real reason for the denial of the claim is likely that it was a ridiculous marketing ploy, not a meaningful health claim.

  19. Bill Minuke says:

    Maybe we can compromise?

    Why not sell Dehydration cure water in the pharmacy, at $25 a bottle, and water with no claims in the water isle for a $1.

    I’m torn, though I hate the idea, I’d love to hear what the non-skeptical/non-scientific response would be.

  20. FillRoy says:

    Skeptvet has it exactly right. This decision reflects the difference between a risk factor and the disease itself. It makes me want to look up how they treat other deficiencies… because it seems like curing and preventing a deficiency have some overlap.