Ben Goldacre - Bad Science

It won’t be even slightly difficult, because this is the only science lesson where I can guarantee that the people making the stupid mistakes won’t be you. And if, by the end, you reckon you might still disagree with me, then I offer you this: you’ll still be wrong, but you’ll be wrong with a lot more panache and flair than you could possibly manage right now.

Ben Goldacre

July 2008

I spend a lot of time talking to people who disagree with me – I would go so far as to say that it’s my favourite leisure activity – and repeatedly I meet individuals who are eager to share their views on science despite the fact that they have never done an experiment . They have never tested an idea for themselves, using their own hands; or seen the results of that test, using their own eyes; and they have never thought carefully about what those results mean for the idea they are testing, using their own brain. To these people ‘science’ is a monolith, a mystery, and an authority, rather than a method.

Dismantling our early, more outrageous pseudoscientific claims is an excellent way to learn the basics of science, partly because science is largely about disproving theories, but also because the lack of scientific knowledge among miracle-cure artistes, marketers and journalists gives us some very simple ideas to test. Their knowledge of science is rudimentary, so as well as making basic errors of reasoning, they also rely on notions like magnetism, oxygen, water, ‘energy’ and toxins: ideas from GCSE-level science, and all very much within the realm of kitchen chemistry.

Detox and the theatre of goo

Since you’ll want your first experiment to be authentically messy, we’ll start with detox. Aqua Detox is a detox footbath, one of many similar products. It has been promoted uncritically in some very embarrassing articles in the Telegraph , the Mirror , the Sunday Times, GQ magazine and various TV shows. Here is a taster from the Mirror .

We sent Alex for a new treatment called Aqua Detox which releases toxins before your eyes. Alex says: ‘I place my feet in a bowl of water, while therapist Mirka pours salt drops in an ionising unit, which will adjust the bioenergetic field of the water and encourage my body to discharge toxins. The water changes colour as the toxins are released. After half an hour, the water’s turned red … she gets our photographer Karen to give it a go. She gets a bowl of brown bubbles. Mirka diagnoses an overloaded liver and lymph – Karen needs to drink less alcohol and more water. Wow, I feel virtuous!’

The hypothesis from these companies is very clear: your body is full of ‘toxins’, whatever those may be; your feet are filled with special ‘pores’ (discovered by ancient Chinese scientists, no less); you put your feet in the bath, the toxins are extracted, and the water goes brown. Is the brown in the water because of the toxins? Or is that merely theatre?

One way to test this is to go along and have an Aqua Detox treatment yourself at a health spa, beauty salon, or any of the thousands of places they are available online, and take your feet out of the bath when the therapist leaves the room. If the water goes brown without your feet in it, then it wasn’t your feet or your toxins that did it. That is a controlled experiment: everything is the same in both conditions, except for the presence or absence of your feet.

There are disadvantages with this experimental method (and there is an important lesson here, that we must often weigh up the benefits and practicalities of different forms of research, which will become important in later chapters). From a practical perspective, the ‘feet out’ experiment involves subterfuge, which may make you uncomfortable. But it is also expensive: one session of Aqua Detox will cost more than the components to build your own detox device, a perfect model of the real one.

You will need:

One car battery charger

Two large nails

Kitchen salt

Warm water

One Barbie doll

A full analytic laboratory (optional)

This experiment involves electricity and water. In a world of hurricane hunters and volcanologists, we must accept that everyone sets their own level of risk tolerance. You might well give yourself a nasty electric shock if you perform this experiment at home, and it could easily blow the wiring in your house. It is not safe, but it is in some sense relevant to your understanding of MMR, homeopathy, post-modernist critiques of science and the evils of big pharma. Do not build it.

When you switch your Barbie Detox machine on, you will see that the water goes brown, due to a very simple process called electrolysis: the iron electrodes rust, essentially, and the brown rust goes into the water. But there is something more happening in there, something you might half-remember from chemistry at school. There is salt in the water. The proper scientific term for household salt is ‘sodium chloride’: in solution, this means that there are chloride ions floating around, which have a negative charge (and sodium ions, which have a positive charge). The red connector on your car battery charger is a ‘positive electrode’, and here, negatively charged electrons are stolen away from the negatively charged chloride ions, resulting in the production of free chlorine gas.

So chlorine gas is given off by the Barbie Detox bath, and indeed by the Aqua Detox footbath; and the people who use this product have elegantly woven that distinctive chlorine aroma into their story: it’s the chemicals, they explain; it’s the chlorine coming out of your body, from all the plastic packaging on your food, and all those years bathing in chemical swimming pools. ‘It has been interesting to see the colour of the water change and smell the chlorine leaving my body,’ says one testimonial for the similar product Emerald Detox. At another sales site: ‘The first time she tried the Q2 [Energy Spa], her business partner said his eyes were burning from all the chlorine that was coming out of her, leftover from her childhood and early adulthood.’ All that chemically chlorine gas that has accumulated in your body over the years. It’s a frightening thought.

But there is something else we need to check. Are there toxins in the water? Here we encounter a new problem: what do they mean by toxin? I’ve asked the manufacturers of many detox products this question time and again, but they demur. They wave their hands, they talk about stressful modern lifestyles, they talk about pollution, they talk about junk food, but they will not tell me the name of a single chemical which I can measure. ‘What toxins are being extracted from the body with your treatment?’ I ask. ‘Tell me what is in the water, and I will look for it in a laboratory.’ I have never been given an answer.

After much of their hedging and fudging, I chose two chemicals pretty much at random: creatinine and urea. These are common breakdown products from your body’s metabolism, and your kidneys get rid of them in urine. Through a friend, I went for a genuine Aqua Detox treatment, took a sample of brown water, and used the disproportionately state-of-the-art analytic facilities of St Mary’s Hospital in London to hunt for these two chemical ‘toxins’. There were no toxins in the water. Just lots of brown, rusty iron.

Now, with findings like these, scientists might take a step back, and revise their ideas about what is going on with the footbaths. We don’t really expect the manufacturers to do that, but what they say in response to these findings is very interesting, at least to me, because it sets up a pattern that we will see repeated throughout the world of pseudoscience: instead of addressing the criticisms, or embracing the new findings in a new model, they seem to shift the goalposts and retreat, crucially, into untestable positions .