What could be so fine… as to be alkaline (Warning: Irony)

Just in case you weren’t confused enough about water, the Alt-oids (my new favourite word for Alt Health boosters) have another Health Mystification Message for you.

In a health context water is a simple story: I would summarize it as “drink clean tap water, or some other liquid, when you feel thirsty”.

However, there is more money in telling people water is a really complicated business, which is what the Alt-oids do. For instance:

“Water” they tell you solemnly “is ONLY good for you when it’s ALKALINE”

Hmmm.

This message has been around for a while, but it has attracted my attention anew as I spotted that one of the online AltMed retailers I occasionally check out is now pushing pH papers as a health aid.

Yes, pH papers. Little books of strips of a special paper that changes colour when you dip it in fluids of different pH (acidity / alkalinity). Apart from in school chemistry, you may have met these papers if you keep tropical fish, or Koi carp.

Now you can buy these papers to check quickly if your body has the appropriate acidity / alkalinity.

 

Er… no you can’t, actually.

You certainly can buy the paper, and test the pH of your spit or wee, which is what the sellers suggest. This will, however, tell you Sweet FA about your “body’s pH balance”.

Apart from anything else, spit and wee have left your body, at least as physiologists and doctors mostly view it. These are secreted fluids. They are just temporarily residing in a compartment which is surrounded by your body. But they are separated from the real inside of your body by a layer of cells, or sometimes several layers.

To test body acid-base status you would have to take an arterial blood sample (to measure your arterial blood gases) – and believe me, you don’t want to do that without a good reason. Especially since, no matter WHAT reading the pH papers give in your spit or wee, there is almost certainly bugger all wrong with your body acid-base status.

You would know if there was, because you would be feeling distinctly ill.

 

First the pH papers… then, the Water AlkalinizerTM…!

Of course, the selling of the pH papers can be just the set-up for a bigger pay-off. This is that you are “too acid”, either because you ”eat acid foods” (a subject for a future post), or because you “drink water that isn’t alkalinized”.

The second of these is a real money-spinner. For example the company I mentioned that is selling the pH papers also sells water alkalinizing systems for anywhere between £ 449 and £ 1249 (roughly 900-2500 $ US). Some health food stores I have seen have these systems and use them to sell “alkalinized water” in bottles, or by the glass.

 

The summary word for all this is: bullshit.

And, to re-emphasise one of my recurring themes, based once again upon confusing you, and convincing you that something normal is BAD for you – the normal here being poor old unloved tap water.

The first, and most blindingly obvious reason, that this is tripe is as follows:

Pure water really doesn’t have a terribly meaningful pH value, and will assume the pH of whatever you mix it with.

So how do you get “alkaline” water?

Well, from small amounts of dissolved salts that “confer” and “hold” the pH (the relative acidity or alkalinity). “Acid rain” is acid because it contains small amounts of salts derived from dissolved acidic gases like SO3 and NO2.

But…. tap water contains rather little in the way of dissolved salts. And the pH of a sample of water can be changed easily – by mixing it with something with a different pH. Like a solution of stomach acid, the stuff your stomach keeps in there to kill any little bugs you swallow that might make you ill, and also to help digest your food.

Furthermore, simple high school / GCSE Chemistry tells you that the “alkaline water” line is a crock. Because the extent to which a solution “holds” its pH value depends on something called the buffer power, which depends specifically on those substances dissolved in the water that can ”buffer” pH. This is something that anyone who did GCSE Chemistry has not only heard of, but has often seen with their own eyes.

Scientists commonly use pH buffers to “set” the pH of solutions they use in experiments to get biological processes to work properly. You need the right pH for the reaction. Different buffer substances have different pH values (or ranges, more accurately) over which they are good at buffering.

In your body, the most important buffer system consists of the “pairing” of carbon dioxide (CO2) and bicarbonate (HCO3-), both of which are closely controlled to keep your “body acid base status” constant and your internal body pH (in your blood, and in your cells) around 7.4 (slightly alkaline).

 

Back to buffering school

To explain buffering simply: Take a weakly-buffered solution, containing a small amount - say 1 mM (1 milliMole per litre, 10-3 Moles / litre) – of a pH buffer substance, and with a pH of 7.0 (neutral). The pH of this weakly buffered solution will fall (go acid) if you drip a drop of strong acid – like HCl, hydrochloric acid – into it. The small amount of pH buffer can’t “defend” the pH of 7.0 very well.

In contrast, a solution of 20 mM pH buffer at pH 7.0 is much more strongly buffered – 20 times as much – and the pH will barely twitch if you drip in the same amount of HCl as in the last example. The pH buffer substance “buffers”- protects – the solution pH of 7.0.

This buffering can also be shown by doing the kind of titration lots of people have done as a school chemistry experiment . You take a solution of a pH buffer in a beaker, add a colour-change pH indicator (something that will change colour when the pH changes substantially from alkaline to acid, or vice versa) and titrate in acid or alkali from a burette. The more concentrated the buffer solution you start with in your beaker, the more acid or alkali you have to add from the burette to get the pH in the beaker to change. Typically you add some, and add some, and add some, and then finally the colour suddenly changes.

What is happening is that as you add acid (say) from the burette it is being “mopped up” by the pH buffer – so that pH only changes a little, and the colour doesn’t change.

Only when all the buffer in the beaker has been consumed in mopping up the added acid does a BIG drop in pH (acidification) occur. And that is when the colour changes.

This simple experiment, which is a kind of special version of the acid-base_titration done by literally millions of kids over the last half-century or more, is actually one of the keys to understanding how your body copes with acids and bases. But more about that in a later post.

From these buffer chemistry examples, it should be intuitively obvious that when you mix two solutions of different pH “more buffer wins”. If you mix a solution containing 20 mM pH buffer at pH X with an equal volume of a solution containing 1 mM buffer at pH Y, the final pH will end up near the starting pH of the 20 mM buffer solution. – pH X.

 

So why does this kick the “Alkaline water” scam into touch?

Well, water will rarely have more than 1-2 mM dissolved salts in it. The main salt that acts as a pH buffer is bicarbonate (HCO3-), derived from dissolved CO2. Let’s say, for the sake or argument, that the water you drink has 1 mM HCO3- in it.

Your body fluids (all of them) usually contain about 20 mM HCO3-. So if I were to mix a litre of water at any pH with a litre of ANY “body fluid” at pH 7.4, the pH of the body fluid would barely be touched.

And there is actually about 45 litres of well-buffered body fluid in my 80 kg body, not one litre. You do the calculation.

In fact, changing the pH of your drinking water won’t even change the pH in your stomach, let alone the rest of you.

Your stomach juice is a rather special secreted fluid; it is a solution of 80-130 mM HCl (hydrochloric acid) and has a pH or about 1-2 (strongly acid). This is its normal pH – with or without your having drunk “alkaline water”. So the pH of the water you drink will not even make a noticeable difference to the acidity of your stomach contents, let alone your body acid-base status.

For this reason, the pH of the water you drink is completely and utterly meaningless. It has hardly any physico-chemical meaning, and it certainly has zero practical significance.

Unless, of course, you are gullilble enough to be conned by the advertising pitch of the “alkaline water” snake oil salesmen.

 

Previous water posts:

Part 3: Glug glug glug – why those eight glasses a day don’t have to be water – or eight


Part 2:
Drinking water can be deadly (not) pt 2: the men in grey suits… are actually on the case


Part 1: Drinking water – or bathing in it – can be deadly (not)

16 Responses to “What could be so fine… as to be alkaline (Warning: Irony)”

  1. gimpy Says:

    Excellent article, however there are public health benefits in increasing the pH of tap water slightly to offset the problem of dissolved lead in drinking water as this rather dense reort explains. Of course this has nothing to do with the ‘body’s pH balance’ but is still likely necessary to help maintain the health of the population.

  2. witchdoctor Says:

    Ah, this is where you hang out, Dr Aust!

    I love your blog, and unlike mine, it contains so much sense that is backed up by the scientific method.

    The Witch Doctor thinks you are filling a very important niche in the Blogosphere. Keep going from strength to strength.

    For me, the bottled water story is really a disconcerting sentinal example of how “The Humankind” creep. I suppose it starts of with some cranky observation that is picked up by business men who are not in the least cranky. They then start the marketing ball rolling and huge numbers of the population are brainwashed into drinking the stuff. Then there is no thinking. No reasoning at all. Just blind acceptance by people who are very capable of thinking and reasoning.

    Ignoring effects on the environment, individuals’ purses etc, I suppose you might regard the bottled water issue as a relatively harmless “creep.” Nevertheless this fault in The Humankind scares this witch witless.

  3. Dr* T Says:

    Preach, Brother Aust, Preach.

    Real chemistry…… Mmmmm…….

  4. draust Says:

    Gimpy

    – thanks for the info on lead – I hadn’t thought of that. I wonder how much lead plumbing is still around? There was a little bit left in my last house that I sold in 2000, so I always used to run the water until it ran “mains cold” Hadn’t heard about solder, though. Anyway, I guess this is one of the reasons the water engineers monitor and if necessary tweak the pH of the domestic supply. So we should probably say that:

    “Inappropriately acid tap water could cause some increased exposure to lead, which is why the pH of your supply will be one of the many things carefully monitored and controlled by the water engineers.”

    When I was reading about “chlorination byproducts”, I was deeply impressed by how much info / literature there was about checking things in the domestic water supply, and assessing and re-assessing risk, and so on. Made me feel quite warm about scientific public servants. Unglamorous work, and invisible to most people, but important.

    The problem in some ways is that a lot of the public seem to fall into one of two camps: either they take clean wholesome tap water utterly for granted (until they have a Summer flood disaster and the army has to show up with the water trucks), or else they think the stuff is no good and that the Govt doesn’t care a stuff if “They” poison us all.

    *sigh*

    Witchdoctor

    – welcome to my ranting corner-shop. Very pleased to have you here. You are being too modest about your blog.

    I find pootle-ing round the the medical blogosphere very interesting, as some of the blogs recapitulate and expand much of what I hear over the cornflakes from ‘Er Indoors. In fact I occasionally post things on the medical blogs paraphrasing her views.

    I do often wonder how GPs in particular deal with all the reality-free “Health Urban Legends” their patients must pick up. I suppose it all just comes under the medical sociology “Health Beliefs” umbrella. I come across enough jaw-dropping misconceptions among the B.Sc. degree students, so I shudder to think what the broader population believes.

    Dr* T

    – Yes, don’t know when I did my first acid-base titration at school, but it was definitely some time in the 70s… *cough*.

    In fact my first degree , also back more years than I care to recall, was Chemistry… though I specialized in bio-organic and biological chemistry, and generally kept as far away from physical chemistry as possible! I remember writing a finals essay comparing the Maxam-Gilbert and the Sanger dideoxy end-termination sequencing methods for DNA, and stuff like that.

    Talking of basic science, one of things that has been interesting about teaching basic physiology to the science and medical students has been just how much of how the human body works you can understand with a decent grasp of school Chemistry and Physics concepts (mostly what I recall as O-level ones). Gas laws, acids and bases, Ohm’s law, osmosis etc etc. Hence those annoying tutor habits of saying “Well, it’s really just V = IR, isn’t it…?” Was just doing this one the other day trying to lead the students through cardiac output and blood pressure. I’m sure it winds them up, but as I get older I find that just encourages me to do it more.

  5. witchdoctor Says:

    Hey, My Black Cat, If you’re going to cut and paste things for me on a Sunday morning while I’m having a long lie, will you learn how to spell!

    A few of the medical establishment have some jaw-dropping misconceptions too, I fear – maybe because they don’t have enough thinking time nowadays and just go along with the flow.

    Some of the topics you tackle remind me very much of a colleague I worked with for a while who had a scientific/statistical/ biological background. He stayed very much in the wings but many kept medics on the straight and narrow with their publications. Everyone knew if his name was on the paper, the work was sound.

  6. gimpy Says:

    DrAust - thanks for the info on lead – I hadn’t thought of that. I wonder how much lead plumbing is still around?

    Apparently about 40% of UK houses have lead pipes.

    Totally with you on the scientific public servants. Several months ago I had a visit from the water board collecting samples from the taps in my house. The lady collecting took the time to explain what she was doing, what they were testing for and how the water was purified. She even gave me a number to call to find out what the composition of my tap water re mineral content and microscopic flora and fauna was.

  7. Patrick Holford and How Super Water Reduces Acidity in the Blood « Holford Watch: Patrick Holford, nutritionism and bad science Says:

    [...] Update: We refer you to Dr Aust’s previous discussion of where you will discover many interesting things about the body’s buffer systems and delight i… [...]

  8. physicsmum Says:

    So many lead pipes?? Egad!!

    Fascinating discussion of water, pH, and so on. Our local tap water has a pH of around 7.6, which I happen to know only because we keep fish, and the pH of the water is rather important to those who actually live in it. I took me quite a while to figure out why our first few goldfish dropped dead within 48 hours of being brought “home”.

    One thing puzzles me though – can anyone explain why, if we are all so acidic and need alkaline water, apple cider vinegar is touted as such a panacea to prevent and cure all sorts of ills? Is there not a slight inconsistency here?

  9. draust Says:

    Inconsistency has never been much of a worry to the Alt.Reality crew, or to purveyors of folk remedies.

    One of more intriguing aspects of CAM, from a strictly anthropological field-work point of view, is to see all the different alternative “modalities” patting one another on the back, when they each have their own largely exclusive belief system that says they, and only they, are in unique possession of THE TRUTH.

    Of course, there is an underlying theme, or rather two. The first unifying factor is that they all tend to dislike conventional science and medicine. The second is that they all believe in a mysterious unmeasurable kind of “life energy” which – surprise surprise – their therapy is particularly attuned to manipulating.

    You might see a parallel here with monotheistic religions, which each tend to think they are uniquely right, but might at a pinch agree that “we all worship the same God, but in our different ways”. The parallel is apt since both religions and Alt Medicine are based on faith, not evidence.

  10. Cooking up arthritis treatments « A canna’ change the laws of physics Says:

    [...] See Orac, HolfordWatch and Dr Aust’s [...]

  11. jacksonskepticalsociety Says:

    Thanks Dr. Aust. I especially loved the explanation in liters there. The sort of thing you can convey in person to someone without any scientific training at all (i.e, the types who generally drink the stuff).

    I buy and sell vegetables for a living and daily am accosted by a new pyramid scheme, miracle fruit, (not the actually miracle fruit, the one that makes all food taste sweet) superfood or alkalizing body scheme. I try explaining how no sane amount of baking soda is going to make a whit of difference to your stomach acid pH, but – fat lot of good it does me. Now I’ll try your technique.

  12. draust Says:

    Thanks. I always reckon a real example with real numbers (or something people are familiar with) is best. True for University students too!

    The superfoods thing is a real refuses-to-die one. Years ago a buddy of mine (a pathologist who has actually been on a couple of TV shows) and I toyed with the idea of writing a “bullshit-free” diet advice book. We ditched the idea because we figured most of what was useful could go on a page, so would hardly stretch to a book. And you can get it down to a line, like Michael Pollan’s famous:

    “Eat food. Not too much. Mainly plants.”

    On water, at Chez Aust we have been through phases of filtering the tap water (with the cheapest possible jug filter), mainly just to make it taste a bit less chlorine-y at times when the municipal people have upped the chlorine levels a bit. But we find just standing it in a jug in the fridge works every bit as well, so we haven’t used a filter for a couple of years. And the idea that somehow your health depends on filtering…. or alkalinization…

    * rolls eyes *

    Good luck with spreading the skepticism!

  13. Defro Says:

    Water machines are a scam. Can’t wait to pay this off for the next year. Thought I was joining a cult….funny my tap boiled faster than the machine. I ask …. why does one need a machine to make water?

  14. Holding back the tide – it’s alkaline, by the way « Dr Aust’s Spleen Says:

    [...] written about how “alkaline water” is a bunch of bullshit and a scam – including by me – there are still preposterous claims for its health benefits everywhere. Blogger Andrew [...]

  15. This week’s Alkaline ASA Adjudication: Alkalized Water not as miraculous as they claim | Josephine Jones Says:

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  16. Manu Says:

    i agreed the body is acidic. but that does’t mean that we should also drink acidic water. nothing wrong with less acidic water i.e. ionized alkaline water.

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