Bad Science - Ben Goldacre

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began to salivate in response to the sound of a bell. Researchers have measured immune system changes in dogs using just flavoured sugar water, once that flavoured water has been associated with immunosuppression, by administering it repeatedly alongside cyclophosphamide, a drug that suppresses the immune system.

      A similar effect has been demonstrated in humans, when the researchers gave healthy subjects a distinctively flavoured drink at the same time as cyclosporin A (a drug which measurably reduces your immune function). Once the association was set up with sufficient repetition, they found that the flavoured drink on its own could induce modest immune suppression. Researchers have even managed to elicit an association between sherbet and natural killer cell activity.

      What does this all mean for you and me?

      People have tended to think, rather pejoratively, that if your pain responds to a placebo, that means it’s ‘all in the mind’. From survey data, even doctors and nurses buy into this canard. An article from the Lancet in 1954—another planet in terms of how doctors spoke about patients—states that ‘for some unintelligent or inadequate patients, life is made easier by a bottle of medicine to comfort the ego’.

      This is wrong. It’s no good trying to exempt yourself, and pretend that this is about other people, because we all respond to the placebo. Researchers have tried hard in experiments and surveys to characterise ‘placebo responders’, but the results overall come out like a horoscope that could apply to everybody: ‘placebo responders’ have been found to be more extroverted but more neurotic, more well-adjusted but more antagonistic, more socially skilled, more belligerent but more acquiescent, and so on. The placebo responder is everyman. You are a placebo responder. Your body plays tricks on your mind. You cannot be trusted.

      How do we draw all this together? Moerman reframes the placebo effect as the ‘meaning response’: ‘the psychological and physiological effects of meaning in the treatment of illness’, and it’s a compelling model. He has also performed one of the most impressive quantitative analyses of the placebo effect, and how it changes with context, again on stomach ulcers. As we’ve said before, this is an excellent disease to study, because ulcers are prevalent and treatable, but most importantly because treatment success can be unambiguously recorded by having a look down there with a gastroscope.

      Moerman examined 117 studies of ulcer drugs from between 1975 and 1994, and found, astonishingly, that they interact in a way you would never have expected: culturally, rather than pharmacodynamically. Cimetidine was one of the first ulcer drugs on the market, and it is still in use today: in 1975, when it was new, it eradicated 80 per cent of ulcers, on average, in the various different trials. As time passed, however, the success rate of cimetidine deteriorated to just 50 per cent. Most interestingly, this deterioration seems to have occurred particularly after the introduction of ranitidine, a competing and supposedly superior drug, onto the market five years later. So the self-same drug became less effective with time, as new drugs were brought in.

      There are a lot of possible interpretations of this. It’s possible, of course, that it was a function of changing research protocols. But a highly compelling possibility is that the older drugs became less effective after new ones were brought in because of deteriorating medical belief in them. Another study from 2002 looked at seventy-five trials of antidepressants over the previous twenty years, and found that the response to placebo has increased significantly in recent years (as has the response to medication), perhaps as our expectations of those drugs have increased.

      Findings like these have important ramifications for our view of the placebo effect, and for all of medicine, since it may be a potent universal force: we must remember, specifically, that the placebo effect—or the ‘meaning effect’—is culturally specific. Brand-name painkillers might be better than blank-box painkillers over here, but if you went and found someone with toothache in 6000 BC, or up the Amazon in 1880, or dropped in on Soviet Russia during the 1970s, where nobody had seen the TV advert with the attractive woman wincing from a pulsing red orb of pain in her forehead, who swallows the painkiller, and then the smooth, reassuring blue suffuses her body … in a world without those cultural preconditions to set up the dominoes, you would expect aspirin to do the same job no matter what box it came out of.

      This also has interesting implications for the transferability of alternative therapies. The novelist Jeanette Winterson, for example, has written in The Times trying to raise money for a project to treat AIDS sufferers in Botswana—where a quarter of the population is HIV positive—with homeopathy. We must put aside the irony here of taking homeopathy to a country that has been engaged in a water war with neighbouring Namibia; and we must also let lie the tragedy of Botswana’s devastation by AIDS, which is so phenomenal—I’ll say it again: a quarter of the population are HIV positive—that if it is not addressed rapidly and robustly the entire economically active portion of the population could simply cease to exist, leaving what would be effectively a non-country.

      Leaving aside all this tragedy, what’s interesting for our purposes is the idea that you could take your Western, individualistic, patient-empowering, anti-medical-establishment and very culturally specific placebo to a country with so little healthcare infrastructure, and expect it to work all the same. The greatest irony of all is that if homeopathy has any benefits at all for AIDS sufferers in Botswana, it may be through its implicit association with the white-coat Western medicine which so many African countries desperately need.

      So if you go off now and chat to an alternative therapist about the contents of this chapter—which I very much hope you will—what will you hear? Will they smile, nod, and agree that their rituals have been carefully and elaborately constructed over many centuries of trial and error to elicit the best placebo response possible? That there are more fascinating mysteries in the true story of the relationship between body and mind than any fanciful notion of quantum energy patterns in a sugar pill?

      To me, this is yet another example of a fascinating paradox in the philosophy of alternative therapists: when they claim that their treatments are having a specific and measurable effect on the body, through specific technical mechanisms rather than ritual, they are championing a very old-fashioned and naïve form of biological reductionism, where the mechanics of their interventions, rather than the relationship and the ceremony, have the positive effect on healing. Once again, it’s not just that they have no evidence for their claims about how their treatments work: it’s that their claims are mechanistic, intellectually disappointing, and simply less interesting than the reality.

       An ethical placebo?

      But more than anything, the placebo effect throws up fascinating ethical quandaries and conflicts around our feelings on pseudoscience. Let’s take our most concrete example so far: are the sugar pills of homeopathy exploitative, if they work only as a placebo? A pragmatic clinician could only consider the value of a treatment by considering it in context.

      Here is a clear example of the benefits of placebo. During the nineteenth-century cholera epidemic, deaths were occurring in the London Homeopathic Hospital at just one third of the rate as in the Middlesex Hospital, but a placebo effect is unlikely to be all that beneficial in this condition. The reason for homeopathy’s success in this case is more interesting: at the time, nobody could treat cholera. So while hideous medical practices such as blood-letting were actively harmful, the homeopaths’ treatments at least did nothing either way.

      Today, similarly, there are often situations where people want treatment, but medicine has little to offer—lots of back pain, stress at work, medically unexplained fatigue and most common colds, to give just a few examples. Going through a theatre of medical treatment, and trying every medication in the book, will give you only side-effects. A sugar pill in these circumstances seems a very sensible option, as long as it can be administered cautiously, and ideally with a minimum of deceit.

      But just as homeopathy has unexpected benefits, so it can have unexpected side-effects. Believing in things which have no evidence carries its own corrosive intellectual side-effects, just as prescribing a pill in itself carries risks: it medicalises problems, as we will see, it can reinforce destructive beliefs about illness, and it can promote

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