Kitabı oku: «Bad Science», sayfa 3

3
The Progenium XY Complex

I have great respect for the manufacturers of cosmetics. They are at the other end of the spectrum from the detox industry: this is a tightly regulated industry, with big money to be made from nonsense, and so we find large, well-organised teams from international biotech firms generating elegant, distracting, suggestive, but utterly defensible pseudoscience. After the childishness of Brain Gym, we can now raise our game.

Before we start, it’s important to understand how cosmetics—and specifically moisturising creams—actually work, because there should be no mystery here. Firstly, you want your expensive cream to hydrate your skin. They all do that, and Vaseline does the job very well: in fact, much of the important early cosmetics research was about preserving the moisturising properties of Vaseline, while avoiding its greasiness, and this technical mountain was scaled several decades ago. Hydrobase, at around £10 for a half-litre tub from your chemist, will do the job excellently.

If you really want to, you can replicate this by making your own moisturiser at home: you’re aiming for a mix of water and oil, but one that’s ‘emulsified’, which is to say, nicely mixed up. When I was involved in hippy street theatre—and I’m being entirely serious here—we made moisturiser from equal parts of olive oil, coconut oil, honey and rosewater (tap water is fine too). Beeswax is better than honey as an emulsifier, and you can modify the cream’s consistency for yourself: more beeswax will make it firmer, more oil will make it softer, and more water makes it sort of fluffier, but increases the risk of the ingredients separating out. Get all your ingredients lightly heated, but separately, stir the oil into the wax, beating all the time, and then stir in the water. Stick it in a jar, and keep for three months in the fridge.

The creams in your local pharmacy seem to go way beyond this. They are filled with magic ingredients: Regenium XY technology, Nutrileum complex, RoC Retinol Correxion, Vita-Niacin, Covabeads, ATP Stimuline and Tenseur Peptidique Végétal. Surely you could never replicate that in your kitchen, or with creams that cost as much by the gallon as these ones cost for a squirt of the tiny tube? What are these magic ingredients? And what do they do?

There are basically three groups of ingredients in moisturising cream. Firstly there are powerful chemicals, like alpha-hydroxy acids, high levels of vitamin C, or molecular variations on the theme of vitamin A. These have genuinely been shown to make your skin seem more youthful, but they are only effective at such high concentrations, or high acidity levels, that the creams cause irritation, stinging, burning and redness. They were the great white hope in the 1990s, but now they’ve all had to be massively watered down by law, unless on prescription. No free lunch, and no effects without side-effects, as usual.

Companies still name them on the label, wallowing in the glory of their efficacy at higher potencies, because you don’t have to give the doses of your ingredients, only their ranked order. But these chemicals are usually in your cream at talismanic concentrations, for show only. The claims made on the various bottles and tubes are from the halcyon days of effective and high-potency acidic creams, but that’s hard to tell, because they are usually based on privately funded and published studies, done by the industry, and rarely available in their complete published forms, as a proper academic paper should be, so that you can check the working. Of course, forgetting that technical stuff, most of the ‘evidence’ quoted in cream adverts is from subjective reports, where ‘seven out of ten people who received free pots of cream were very pleased with the results’.

The second ingredient in almost all posh creams is one which does kind of work: cooked and mashed-up vegetable protein (hydrolysed X-microprotein nutricomplexes, Tenseur Peptidique Végétal, or whatever they’re calling them this month). These are long, soggy chains of amino acids, which swim around in the cream, languorously stretched out in the moistness of it all. When the cream dries on your face, these long, soggy chains contract and tighten: the slightly unpleasant taut sensation you get on your face when you wear these creams is from the protein chains contracting all over your skin, which temporarily shrinks your finer wrinkles. It is a fleeting but immediate pay-off from using the expensive creams, but it wouldn’t help you choose between them, since almost all of them contain mashed-up protein chains.

Finally there is the huge list of esoteric ingredients, tossed in on a prayer, with suggestive language elegantly woven around them in a way that allows you to believe that all kinds of claims are being made.

Classically, cosmetics companies will take highly theoretical, textbookish information about the way that cells work—the components at a molecular level, or the behaviour of cells in a glass dish—and then pretend it’s the same as the ultimate issue of whether something makes you look nice. ‘This molecular component,’ they say, with a flourish, ‘is crucial for collagen formation.’ And that will be perfectly true (along with many other amino acids which are used by your body to assemble protein in joints, skin, and everywhere else), but there is no reason to believe that anyone is deficient in it, or that smearing it on your face will make any difference to your appearance. In general, you don’t absorb things very well through your skin, because its purpose is to be relatively impermeable. When you sit in a bath of baked beans for charity you do not get fat, nor do you start farting.

Despite this, on any trip to the chemist (I recommend it) you can find a phenomenal array of magic ingredients on the market. Valmont Cellular DNA Complex is made from ‘specially treated salmon roe DNA’ (‘Unfortunately, smearing salmon on your face won’t have quite the same effect,’ said The Times in their review), but it’s spectacularly unlikely that DNA—a very large molecule indeed—would be absorbed by your skin, or indeed be any use for the synthetic activity happening in it, even if it was. You’re probably not short of the building blocks of DNA in your body. There’s a hell of a lot of it in there already.

Thinking it through, if salmon DNA was absorbed whole by your skin, then you would be absorbing alien, or rather fish, design blueprints into your cells—that is, the instructions for making fish cells, which might not be helpful for you as a human. It would also be a surprise if the DNA was digested into its constituent elements in your skin (your gut, though, is specifically adapted for digesting large molecules, using digestive enzymes which break them up into their constituent parts before absorption).

The simple theme running through all these products is that you can hoodwink your body, when in reality there are finely tuned ‘homeostatic’ mechanisms, huge, elaborate systems with feedback and measuring devices, constantly calibrating and recalibrating the amounts of various different chemical constituents being sent to different parts of your body. If anything, interfering with that system is likely to have the opposite of the simplistic effects claimed.

As the perfect example, there are huge numbers of creams (and other beauty treatments) claiming to deliver oxygen directly to your skin. Many of the creams contain peroxide, which, if you really want to persuade yourself of its efficacy, has a chemical formula of H₂O₂, and could fancifully be conceived of as water ‘with some extra oxygen’, although chemical formulae don’t really work that way—after all, a pile of rust is an iron bridge ‘with some extra oxygen’, and you wouldn’t imagine it would oxygenate your skin.

Even if we give them the benefit of the doubt and pretend that these treatments really will deliver oxygen to the surface of the skin, and that this will penetrate meaningfully into the cells, what good would that do? Your body is constantly monitoring the amount of blood and nutrients it’s supplying to tissues, and the quantity of tiny capillary arteries feeding a given area, and more vessels will grow towards areas with low oxygen, because that is a good index of whether more blood supply is needed. Even if the claim about oxygen in cream penetrating your tissues were true, your body would simply downregulate the supply of blood to that part of skin, scoring a homeostatic own goal. In reality, hydrogen peroxide is simply a corrosive chemical that gives you a light chemical burn at low strengths. This might explain that fresh, glowing feeling.

These details generalise to most of the claims made on packaging. Look closely at the label or advert, and you will routinely find that you are being played in an elaborate semantic game, with the complicity of the regulators: it’s rare to find an explicit claim, that rubbing this particular magic ingredient on your face will make you look better. The claim is made for the cream as a whole, and it is true for the cream as a whole, because as you now know, all moisturising creams—even a cheap litre tub of Diprobase—will moisturise.

Once you know this, shopping becomes marginally more interesting. The link between the magic ingredient and efficacy is made only in the customer’s mind, and reading through the manufacturer’s claims you can see that they have been carefully reviewed by a small army of consultants to ensure that the label is highly suggestive, but also—to the eye of an informed pedant—semantically and legally watertight. (If you want to make a living in this field, I would recommend the well-trodden career path: a spell in trading standards, advertising standards, or any other regulatory body, before going on to work as a consultant to industry.)

So what’s wrong with this kind of spin? We should be clear on one thing: I’m not on a consumer crusade. Just like the National Lottery, the cosmetics industry is playing on people’s dreams, and people are free to waste their money. I can very happily view posh cosmetics—and other forms of quackery—as a special, self-administered, voluntary tax on people who don’t understand science properly. I would also be the first to agree that people don’t buy expensive cosmetics simply because they have a belief in their efficacy, because it’s ‘a bit more complicated than that’: these are luxury goods, status items, and they are bought for all kinds of interesting reasons.

But it’s not entirely morally neutral. Firstly, the manufacturers of these products sell shortcuts to smokers and the obese; they sell the idea that a healthy body can be attained by using expensive potions, rather than simple old-fashioned exercise and eating your greens. This is a recurring theme throughout the world of bad science.

More than that, these adverts sell a dubious world view. They sell the idea that science is not about the delicate relationship between evidence and theory. They suggest, instead, with all the might of their international advertising budgets, their Microcellular Complexes, their Neutrillium XY, their Tenseur Peptidique Végétal and the rest, that science is about impenetrable nonsense involving equations, molecules, sciencey diagrams, sweeping didactic statements from authority figures in white coats, and that this sciencey-sounding stuff might just as well be made up, concocted, confabulated out of thin air, in order to make money. They sell the idea that science is incomprehensible, with all their might, and they sell this idea mainly to attractive young women, who are disappointingly underrepresented in the sciences.

In fact, they sell the world view of ‘Teen Talk Barbie’ from Mattel, who shipped with a sweet little voice circuit inside her so she could say things like, ‘Math class is tough!’, ‘I love shopping!’ and ‘Will we ever have enough clothes?’ when you pressed her buttons. In December 1992 the feminist direct-action Barbie Liberation Organization switched the voice circuits of hundreds of Teen Talk Barbies and GI Joe dolls in American shops. On Christmas Day Barbie said ‘Dead men tell no lies’ in a nice assertive voice, and the boys got soldiers under the tree telling them ‘Math class is tough!’ and asking ‘Wanna go shopping?’

The work of the BLO is not yet done.

4
Homeopathy

And now for the meat. But before we take a single step into this arena, we should be clear on one thing: despite what you might think, I’m not desperately interested in Complementary and Alternative Medicine (a dubious piece of phraseological rebranding in itself). I am interested in the role of medicine, our beliefs about the body and healing, and I am fascinated—in my day job—by the intricacies of how we can gather evidence for the benefits and risks of a given intervention.

Homeopathy, in all of this, is simply our tool.

So here we address one of the most important issues in science: how do we know if an intervention works? Whether it’s a face cream, a detox regime, a school exercise, a vitamin pill, a parenting programme or a heart-attack drug, the skills involved in testing an intervention are all the same. Homeopathy makes the clearest teaching device for evidence-based medicine for one simple reason: homeopaths give out little sugar pills, and pills are the easiest thing in the world to study.

By the end of this section you will know more about evidence-based medicine and trial design than the average doctor. You will understand how trials can go wrong, and give false positive results, how the placebo effect works, and why we tend to overestimate the efficacy of pills. More importantly, you will also see how a health myth can be created, fostered and maintained by the alternative medicine industry, using all the same tricks on you, the public, which big pharma uses on doctors. This is about something much bigger than homeopathy.

What is homeopathy?

Homeopathy is perhaps the paradigmatic example of an alternative therapy: it claims the authority of a rich historical heritage, but its history is routinely rewritten for the PR needs of a contemporary market; it has an elaborate and sciencey-sounding framework for how it works, without scientific evidence to demonstrate its veracity; and its proponents are quite clear that the pills will make you better, when in fact they have been thoroughly researched, with innumerable trials, and have been found to perform no better than placebo.

Homeopathy was devised by a German doctor named Samuel Hahnemann in the late eighteenth century. At a time when mainstream medicine consisted of blood-letting, purging and various other ineffective and dangerous evils, when new treatments were conjured up out of thin air by arbitrary authority figures who called themselves ‘doctors’, often with little evidence to support them, homeopathy would have seemed fairly reasonable.

Hahnemann’s theories differed from the competition because he decided—and there’s no better word for it—that if he could find a substance which would induce the symptoms of a disease in a healthy individual, then it could be used to treat the same symptoms in a sick person. His first homeopathic remedy was Cinchona bark, which was suggested as a treatment for malaria. He took some himself, at a high dose, and experienced symptoms which he decided were similar to those of malaria itself:

My feet and finger-tips at once became cold; I grew languid and drowsy; my heart began to palpitate; my pulse became hard and quick; an intolerable anxiety and trembling arose … prostration … pulsation in the head, redness in the cheek and raging thirst … intermittent fever … stupefaction … rigidity…

and so on.

Hahnemann assumed that everyone would experience these symptoms if they took Cinchona (although there’s some evidence that he just experienced an idiosyncratic adverse reaction). More importantly, he also decided that if he gave a tiny amount of Cinchona to someone with malaria, it would treat, rather than cause, the malaria symptoms. The theory of ‘like cures like’ which he conjured up on that day is, in essence, the first principle of homeopathy.*

Giving out chemicals and herbs could be a dangerous business, since they can have genuine effects on the body (they induce symptoms, as Hahnemann identified). But he solved that problem with his second great inspiration, and the key feature of homeopathy that most people would recognise today: he decided—again, that’s the only word for it—that if you diluted a substance, this would ‘potentise’ its ability to cure symptoms, ‘enhancing’ its ‘spirit-like medicinal powers’, and at the same time, as luck would have it, also reducing its side-effects. In fact he went further than this: the more you dilute a substance, the more powerful it becomes at treating the symptoms it would otherwise induce.

Simple dilutions were not enough. Hahnemann decided that the process had to be performed in a very specific way, with an eye on brand identity, or a sense of ritual and occasion, so he devised a process called ‘succussion’. With each dilution the glass vessel containing the remedy is shaken by ten firm strikes against ‘a hard but elastic object’. For this purpose Hahnemann had a saddlemaker construct a bespoke wooden striking board, covered in leather on one side, and stuffed with horsehair. These ten firm strikes are still carried out in homeopathy pill factories today, sometimes by elaborate, specially constructed robots.

Homeopaths have developed a wide range of remedies over the years, and the process of developing them has come to be called, rather grandly, ‘proving’ (from the German Prufung). A group of volunteers, anywhere from one person to a couple of dozen, come together and take six doses of the remedy being ‘proved’, at a range of dilutions, over the course of two days, keeping a diary of the mental, physical and emotional sensations, including dreams, experienced over this time. At the end of the proving, the ‘master prover’ will collate the information from the diaries, and this long, unsystematic list of symptoms and dreams from a small number of people will become the ‘symptom picture’ for that remedy, written in a big book and revered, in some cases, for all time. When you go to a homeopath, he or she will try to match your symptoms to the ones caused by a remedy in a proving.

There are obvious problems with this system. For a start, you can’t be sure if the experiences the ‘provers’ are having are caused by the substance they’re taking, or by something entirely unrelated. It might be a ‘nocebo’ effect, the opposite of placebo, where people feel bad because they’re expecting to (I bet I could make you feel nauseous right now by telling you some home truths about how your last processed meal was made); it might be a form of group hysteria (‘Are there fleas in this sofa?’); one of them might experience a tummy ache that was coming on anyway; or they might all get the same mild cold together; and so on.

But homeopaths have been very successful at marketing these ‘provings’ as valid scientific investigations. If you go to Boots the Chemist’s website, www.bootslearningstore.co.uk, for example, and take their 16-plus teaching module for children on alternative therapies, you will see, amongst the other gobbledegook about homeopathic remedies, that they are teaching how Hahnemann’s provings were ‘clinical trials’. This is not true, as you can now see, and that is not uncommon.

Hahnemann professed, and indeed recommended, complete ignorance of the physiological processes going on inside the body: he treated it as a black box, with medicines going in and effects coming out, and championed only empirical data, the effects of the medicine on symptoms (‘The totality of symptoms and circumstances observed in each individual case,’ he said, ‘is the one and only indication that can lead us to the choice of the remedy’).

This is the polar opposite of the ‘Medicine only treats the symptoms, we treat and understand the underlying cause’ rhetoric of modern alternative therapists. It’s also interesting to note, in these times of ‘natural is good’, that Hahnemann said nothing about homeopathy being ‘natural’, and promoted himself as a man of science.

Conventional medicine in Hahnemann’s time was obsessed with theory, and was hugely proud of basing its practice on a ‘rational’ understanding of anatomy and the workings of the body. Medical doctors in the eighteenth century sneeringly accused homeopaths of ‘mere empiricism’, an over-reliance on observations of people getting better. Now the tables are turned: today the medical profession is frequently happy to accept ignorance of the details of mechanism, as long as trial data shows that treatments are effective (we aim to abandon the ones that aren’t), whereas homeopaths rely exclusively on their exotic theories, and ignore the gigantic swathe of negative empirical evidence on their efficacy. It’s a small point, perhaps, but these subtle shifts in rhetoric and meaning can be revealing.