Archive for March, 2008

An imperfect (Q) ten

March 19, 2008

This has been another of those fortnights of “deja-vu all over again” (in baseball legend Yogi_Berra’s famous phrase), as the newspapers have been full of plugs for “Miracle Supplement” Coenzyme_Q10.

Boots are having a big marketing push for their latest formulation of CoQ10, claiming that it will give you lots of energy, and even offering “your money back if not satisfied” (Boots apparently have confidence in the power of wishful thinking and the placebo effect).

Boots’ press release and promo campaign seems to have generated the usual crop of dim features in the “Health and Beauty” or “Lifestyle” sections of several of the UK national papers. Most of these features, as both Ben Goldacre and David Colquhoun have deconstructed, revolve about deliberate overuse of that misunderstood word, and favourite Alt Health trope, “energy”.

[The mention of “Energy” is, of course, a surefire stand-by for a good dose of health page waffle. The very word drips waffle, and probably scores you a Canard or two on the Quackometer. Wikipedia lists a bunch of usages for “energy”. It is no accident that half of them relate to favourite Alt Health Woo-themes like “spirituality”.]

If you are especially unlucky, your newspaper may have leavened the energy-waffle with what we call a “Media doc filler”, or “MDF” for short. For those that are unfamiliar with this genre of newspaper space-filling, an MDF often accompanies a feature on a new supplement , or heavily marketed medicine, and goes something like this:

——————————————————————————————–

NanoNutri LipoBalls – A Doctor Writes:

“As a national newspaper doctor I am frequently asked by the nice chaps and chap-ettes on the “Nutrition and Health“ pages: “can we have a quick 300 words to pad out this press release – sorry, story – about some expensive supplement?”

My answer is always “Only if it will help tackle my low financial energy levels, sunshine”. And aren’t low energy levels something we all increasingly suffer from in today’s non-stop energy-sapping 24-hr world?

It is amazing these days how often my patients seem to wish they had more energy.

I don’t know how many times I have heard a patient say to me “I feel worn out, doctor”. To which I usually respond: “That sounds very much like what we doctors call an “Energy Deficiency” – fifty pounds, thank you, pay the receptionist on your way out. Next!”

Twenty thousand or so years ago, a quick sabre-toothed tiger hunt would have left primitive man with a huge appetite, but after a haunch of roast mammoth and 12 hrs solid sleep he would have been ready for anything. However, nowadays we work so much we hardly have time to eat, or to sleep more than five hrs a night – and when we do eat it’s more likely to be a hurried prawn sandwich than mammoth supreme.

Faced with that, who couldn’t do with a bit of a pick-me-up? And new NanoNutri LipoBalls® are formulated with EnergyNano’s patented Fast Liposome Intra-Mitochondrial Formula Liquid-energy AntioxidantMax technology, or “FLIM-FLAM” for short, to get extra-fast to the parts other Energy supplements cannot reach.

So how were the results? Well, within a few days of first encountering NanoNutri LipoBalls®, things were certainly looking up. Having banked a pleasingly large cheque, I found that my energy levels had been dramatically improved. A spring had returned to my step, a twinkle to my eye, and a satisfying bulge to my wallet.

(Is that enough?)

A Doctor”

——————————————————————————-

Now, while I may have been mysteriously “channeling” Private Eye’s fictional Dr Utterfraud here, I am not exaggerating by all that much. If you don’t believe me, read this.

Where does all this hype come from? Well, you can find plenty about CoQ10 and what it does on Wikipedia, but a brief summary would be that it is a chemical substance that is important for how your mitochondria work. Mitochondria are your cells’ “powerhouses”, converting chemical energy (substrates, a posh biochemical word for “fuel substances”) into carbon dioxide and water, with the concomitant production of the cell’s “energy currency” molecule ATP.

 

Here you see the beauty of the CoQ10 sales spin. The description above mentions energy – here in its scientific sense. So voila – mention that CoQ10 helps produce “energy” and it is an instant sell. Everyone would like to have more “energy” (in its non-scientific sense of “get up and go”, the sort that parents wonder at in their small children while bemoaning that they don’t have themselves).

All you have to do is plant in peoples’ minds the two ideas that:

 

  1. CoQ10 has something to do with energy (true)

  1. Energy (scientific sense) = energy (vernacular sense) (false)

 

and the result is Ker-chinggg – cash registers jingle.

Now, an interesting aspect of the current “Q10 buzz” is that CoQ10 was discovered fifty years ago. It is not new. And it has been around, as a supplement, for at least 15 and probably closer to 25 years. Very “Not new”, in fact. And it has been tried as a therapy or “performance enhancer” in all sorts of studies - on various diseases, from receding gums to cardiovascular problems to Alzheimer’s, on exercise tolerance and performance etc etc.

So what were the results of these studies? Did they show Q10 was the miracle supplement the current crop of stories seem to be claiming?

The answer is “No”. The studies are inconsistent, with the usual problem of small sample size and lack of “blinding”. But the scientific / medical consensus, which you can find a good summary of here, is that there is basically no indication to take CoQ10 even if you are ill, let alone if you are well.

This is actually an object lesson in the different kinds of evidence that one can have for therapies, including pills, and why some types of evidence are more reliable than others. The “hierarcy” of evidence often used nowadays to decide if treatments can be viewed as actually working (and hence can be recommended for widespread adoption as part of medicine), is shown below. This hierarchy allots higher “levels” (essentially “greater reliability”) of evidence to randomized controlled trials (RCTs), and the highest level of all to “Systematic review (with homogeneity) of RCTs”. This last means when you look systematically at all the RCTs together, if you find that the treatment is consistently coming out as effective then it is a very good bet that it really works.

Various other kinds of studies are less convincing than this - a single, but good trial scores grade 1b, a not-so-well-done RCT scores grade 2b.

Figure: Oxford Centre for Evidence-based Medicine Levels of Evidence (May 2001)

(via Dr Kimball Attwood’s wonderful post on evidence based medicine and Alternative medicine here)

Level

Therapy/Prevention, Aetiology/Harm

1a

Systematic Review (with homogeneity*) of RCTs

1b

Individual RCT (with narrow Confidence Interval‡)

1c

All or none§

2a

SR (with homogeneity*) of cohort studies

2b

Individual cohort study (including low quality RCT; e.g., <80% follow-up)

2c

“Outcomes” Research; Ecological studies

3a

SR (with homogeneity*) of case-control studies

3b

Individual Case-Control Study

4

Case-series (and poor quality cohort and case-control studies§§)

5

Expert opinion without explicit critical appraisal, or based on physiology, bench research or “first principles”

Studies which have designs OTHER than a randomized controlled trial score lower. In particular, studies whose design means they tend to be relatively UNreliable (often because they are contaminated by ”expectancy_effects”, by selection_bias relating to the participants, or by regression_toward_the_mean) are down in grade 4. Here the way the trials is done is often “give people the pill, with no control group and no placebo, and then ask if they think taking it made them feel better”.

The similarity between this last one and a “money back guarantee” if you didn’t think Q10 supplements gave you more energy is not a coincidence.

Finally, the idea that “because this works in a dish it will work in people”, much used to plug Alternative medicines, is down at grade 5, as is another familiar one, “this works because this or that expert guru says it does, regardless of the lack of any critical appraisal of the evidence to back it up”.

The talking-up of CoQ10 in leaflets, and on websites, and now in the papers, is mostly a fancy example of the “because it works in a dish” (level 5) argument down at the bottom of the pile. And most of the existing CoQ10 trials in humans, which some of the stories refer to en passant, are down at grade 4. Reviews of the trial evidence on CoQ10 tend to be (at best) in grade 3a, since the trials usually lack “homogeneity” (i.e. the results are inconsistent).

The upshot is that Q10 would not get licenced for use as a medicine in any common condition, because the evidence that it produces benefits simply is not good enough. The only exceptions, thus far, are very rare, mostly genetic, and specifically mitochondrial diseases.

 

Repeat: For all the other stuff, the evidence simply is not there.

Incidentally, this is true even if you take something where there seems to be a really appealingly plausible scientific rationale for using CoQ10 (grade 5). The best-known example is probably in people taking statins. Your cells make their own CoQ10 – another reason why the need for supplements is very dubious – and the biosynthetic pathway leading to CoQ10 is “shared” (part of it) with cholesterol biosynthesis. Hence the common website claim that if you are taking cholesterol-lowering statins (which partially inhibit a key enzyme in the pathway) then you “need” to supplement your CoQ10.

Sounds plausible. However, it turns out that the trial evidence is not running in favour of CoQ10 supplementation even when people are taking statins, and even in the subgroup of people on statins who have symptoms suggestive of statin side effects (Coracle has written about this at length). So if CoQ10 were to be marketed as a medicine for this statin setting there would not be nearly enough evidence to approve it. This points up – again – the difference between the efficacy standards required for drugs (there are some) and supplements (there aren’t any).

Of course, if there isn’t convincing evidence that CoQ10 makes a difference even in a situation where using it might seem biochemically highly “plausible”, you can bet your mortgage there is bugger all reason for normal people to take it on the off chance that it will do something. Apart from making the supplement peddlers considerably richer,

But…. To keep repeating the obvious, you don’t need any evidence to market a supplement. You only need to show that it doesn’t seem to be toxic.

 

Plus ca change, plus c’est la meme chose

Getting back to “déjà vu all over again”, the CoQ10 thing prompted me to have a dig through my own files. Back in the mid 1990s – about 1995 or 96, I think – I remember seeing a big display of CoQ10 pills in Boots. (Yes, amazingly they already sold them back then). As a ”recovering Biochemist”, this piqued my interest, so a year or two later I started setting medical student dissertation topics (i.e. reviews of the scientific literature) about supplements and alternative remedies.

Which leads me to this: lurking in my files is a dissertation a first year medical student wrote for me back in 1999 (sic) on:

 

“Coenzyme Q10: snake oil or medicine?”

[The student would have graduated in 2003 and is now, I guess, a junior doctor]

A couple of sample quotations:

”While some adverts for CoQ10 make use of anecdotal evidence from individuals testifying to “the miracle of Q10”, others make weightier-sounding allusions to scientific studies. But to what extent are claims made by the supplement industry upheld by scientific studies?”

A question Dr Thomas Stuttaford, Boots, and various health page journalists appear to have forgotten how to formulate. The answer, as we have already seen above, is “Not very much, if at all”.

Another bit from the student’s work discussing the “lifestyle-enhancing” claims for Q10:

”…What constitutes “normal” levels [of CoQ10] is of course open to debate. While no frank CoQ10 deficiency has yet been described, Folkers claims that suboptimal levels of CoQ10 are universal. There is, however, little current evidence to suggest that CoQ10 supplementation benefits the healthy individual.

Despite this, many people do take CoQ10, seemingly unconcerned about the lack of scientific evidence to support the anti-ageing, energy-boosting, flab-fighting, brain-stimulating and sex-life enhancing claims the adverts boast.

Adverts on the Internet may allude to scientific studies but generally fail to provide references and information is sometimes presented in a misleading way. They generally use a didactic tone and sometimes warp information to [persuade people] to buy their product, as demonstrated by the following advert:

”The body’s levels of CoQ10 decline with age; therefore it is necessary to supplement the diet. Food does not contain significant amounts of CoQ10 and the body des not produce enough CoQ10 on its own, so supplementation is imperative in order to have adequate amounts of it” (Emphasis added).

[Furthermore], findings of low levels of CoQ10 in disease states do not necessarily imply that low levels will lead to these diseases, as some adverts claim.

All [this] renders consumers vulnerable, all the more worrying since direct-to-consumer advertising of [nutriceutical] products is now big business. …”

 

Hmmm. Now, it is fair to say this was a bright student, even by the normal bright standards of first year medics. But… armed with essentially A level-plus-a-bit scientific knowledge, a first-rate brain, and a questioning mindset, s/he could see through the claims of the supplement peddlers. So one might expect that Boots’ “panel of experts”, Ann Walker PhD, and even Dr Stuttaford ought to be able to take a slightly more balanced view.

 

…If they wanted to.

And there’s the catch.

If they wanted to.

 

Boots, remember, are trying to sell you something. So is Ann Walker. Why should a seller tell the truth if spin sells better? And Dr Stuttaford is making a living cranking out re-worded press release bumpf.

Plus – there is nothing to stop them. Provided they avoid making directly and demonstrably false claims – as opposed to writing ambiguous things that will merely encourage readers to draw obvious but erroneous conclusions – they can say what they like.

As ever, caveat emptor. And that means you.

What gets children into science? The stuff we’re cutting… like Jodrell Bank

March 8, 2008

 

Dr Aust is, in case you hadn’t guessed by now, A Grumpy Old Fart.

Well, a Grumpy Middle-aged Fart, to be exact.

(I have searched high and low for an age definition of “middle aged” that WON’T include me, but I have finally had to admit defeat.)

So I am middle aged.

BUT: once I was young. Honest.

One of the things middle-aged people with Blogs do a fair bit of is wondering how they got to where they have ended up, life and career-wise.

So… how did I get interested in science?

Well, I did have a relative in the family generation above me who was a scientist, but I never had much idea what he did, except that it took place somewhere called a “laboratory”. Said relative was once persuaded to come to my school and show us kids a laser, and a hologram, which was quite neat. And he once tried to teach me physics, which ended in tears after about an hour. I have never been much good at physics.

But I’m pretty sure that wasn’t why I got interested.

No, personally I blame, inter alia, Gerald_Durrell’s books about animals, John F Kennedy and the manned space programme, Gene “Star Trek” Roddenberry, Look_and_Learn magazine and the sadly-no-longer-extant London_Planetarium.

Because: how could any small boy NOT be interested in animals, and fossils, and dinosaurs, and rocks, and volcanoes, and moon rockets, and space travel, and stars?

The path from there to my corner of cell biology and physiology is a bit tortuous. But I still think that the natural world, and all the remarkable things in it, on it, under it and visible from it, are where science starts to exert a fascination on the young. Junior Aust, now approaching four, is being shown how to plant seeds, and told (as much as possible) how the cartoons she likes to watch on Youtube arrive on the screen down the telephone wires, and where real tigers live (she is fond of tigers).

 

But what if Pop Idol is more interesting?

Common to most scientists I know, when feeling pessimistic, is the view that if we can’t get children interested in the natural world, then we will not be able to get them interested in science later on. With all kinds of (bad) consequences.

So any thing, or place, that tries to get children interested is A Good Thing, in my book.

Oddly, it seems the UK Government does not agree, despite all the tedious oily “Of Course”-ing about how vitally important science is to the nation’s future prosperity.

Thirty odd miles down the road from Chez Dr Aust is the Jodrell_Bank Observatory. This is a major site for UK astrophysics research, and specifically for radio astronomy. The Lovell_telescope, which is 50 yrs old, is one of those objects/ images that almost personify scientific research, testifying to the slightly bonkers constructional genius of some scientists and their endearingly obsessed determination to find things out. It must be one of the most recognisable objects associated with UK science. I first saw it when I was about 30, but I had seen a picture of it in a book when I was no more than 5 years old. And it is undeniably impressive – I’ve seen the Jodrell telescope, and Dolly_the_sheep, close-up, and the telescope wins hands down.

But Jodrell Bank is more than that. It also has a science visitors’ centre. And a Planetarium (sadly currently shut for repairs). And a 30+ acre garden and arboretum you can wander round with over 3000 plant species. And it is reasonably cheap to get into, even if you take an entire family.

So to summarize: cheek by jowl with a place where real scientists do real science, a national centre yet, you can take the children to a stardome simulation, or wander the garden with them and look at the trees and plants. You, and they, can stand right underneath the Lovell telescope and test the echo.

The Jodrell Visitors’ Centre also do science outreach events. They host school visits, for children of all ages. If you take a Physics A level group there, you can have real professional research astrophysicist come and talk to the class. The Observatory also teaches undergraduate, and PhD, students.

And so on, and so on.

In an era where we science-geeks are continually told to do our bit to inform the public about what we do, and “engage” with them, you would have thought Jodrell exemplified exactly how these things ought to be done.

 

So what is happening?

Whoops – the government is cutting the funding for the major current research project at Jodrell. Because they have screwed up the budgeting.

 

The project this pays for is called “MERLIN”, which stands for Multi-Element Radio Linked Interferometer Network. Essentially it is a network of radio telescopes around the UK linked together. By linking them they can do radio-astronomy as if they were a super-large radio telescope. That is basically as much of it as I understand – I told you I was terrible at physics – so if you want to know more start reading here.

MERLIN cost £ 9 million or so to build, and costs £ 2.7 M a year to run, money that had been promised by a UK Govt Agency called the Science and Technology Facilities Council.(STFC). However, despite all the endless puffing about “record funding levels” and “a Golden Age for UK science funding” coming from Govt spokesmen, the STFC has had a 25% cut in its budget for these major projects and facilities, and the axe is now starting to fall.

Big cuts are to be made. And they say the MERLIN programme will be one of the things to go.

[The more cynical among you might think that cutting MERLIN possibly reflects two other things: first, the Govt doesn’t see the point of astronomy and astrophysics research, as it doesn’t have many wealth-generating spin-offs; and second, Jodrell Bank is in the North of England, rather than in the (electorally important) South-East.]

Obviously the cutting of MERLIN will be terrible news for the radio astronomy people. And for astrophysics generally. And it will waste the money already invested in building the thing.

But it will do more than that. Without the MERLIN project, it is a good bet that the entire Jodrell site will become uneconomic to run. Given that Jodrell’s parent University of Manchester has been having a bit of a financial belt-tightening, they are hardly going to be finding a spare £ 2.7 million a year.

So there is a very really chance that a centre of scientific excellence with a sixty-year tradition, an icon of UK science, a popular visitor attraction, and a place that every years encourages many thousands of kids to take a greater interest in science and the natural world, will shut. And all while ministers continue to make smarmy speeches full of ringing phrases about creating:

“…a society that is excited about science, values its importance, feels confident in its use, and supports a representative, well-qualified scientific workforce”.

 

Ian Pearson, Minister for Science and Innovation, speaking at the launch of the Public Engagement Beacon Scheme on 30 Jan 2008.

 

Nothing like “Joined-up thinking” in government, eh?

 

- I will leave you to think about that last one.

 

PS If you agree with me that cutting MERLIN and potentially shutting down the Jodrell Observatory is an utterly f*!ckwitted idea, and would like to tell the (Sub) Prime Minister what you think, there is an e-Petition you can sign here.

 

EDIT - Good grief – I find myself agreeing with something written in the Peoples’ Medical Journal, I mean, the Daily Mail. They have a good article about Jodrell, and its founder Bernard Lovell, here.

 

And finally…

A HANDY GUIDE to some of the things you can get for £ 2.7 Million:

- Annual cost to taxpayer of the MERLIN project at Jodrell Bank observatory

- Approximate amount of expenses claimed last year by cabinet ministers

- 40% of the cost of the recent refurbishment of the House of Commons wine cellars*

- Annual salaries of four average Premiership footballers (approx £ 0.65 million pa each)

- Amount Chelsea football star Frank Lampard Jr, and TV Personawity Jonathan Ross, are each rumoured to earn in around five months.

- Approximate cost of British military spending on operations in Iraq and Afghanistan every SEVEN HOURS**

*See 6th March entry here

**Based on March 10th figures from House of Commons Defence Ctte giving an estimated cost of £ 3.3 Billion for the current financial year. Note that recent work by economists (e..g Nobel Prizewinner Prof Joseph Stiglitz) looking at US spending, and estimating “indirect” costs as well as directly attributable ones, suggest that the true cost may be several times higher than the “official” estimates.

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

March 1, 2008

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)


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