Bad Science

by Ben Goldacre

In terms of basic human biochemistry, detox is a meaningless concept. It doesn’t cleave nature at the joints. There is nothing on the ‘detox system’ in a medical textbook. That burgers and beer can have negative effects on your body is certainly true, for a number of reasons; but the notion that they leave a specific residue, which can be extruded by a specific process, a physiological system called detox, is a marketing invention. If you look at a metabolic flow chart, the gigantic wall-sized maps of all the molecules in your body, detailing the way that food is broken down into its constituent parts, and then those components are converted between each other, and then those new building blocks are assembled into muscle, and bone, and tongue, and bile, and sweat, and bogey, and hair, and skin, and sperm, and brain, and everything that makes you you, it’s hard to pick out one thing that is the ‘detox system’. Because it has no scientific meaning, detox is much better understood as a cultural product. Like the best pseudoscientific inventions, it deliberately blends useful common sense with outlandish, medicalised fantasy.

As a World Bank report put it in 1999: These cleansing and purification rituals for child soldiers have the appearance of what anthropologists call rites of transition. That is, the child undergoes a symbolic change of status from someone who has existed in a realm of sanctioned norm-violation or norm-suspension (i.e. killing, war) to someone who must now live in a realm of peaceful behavioural and social norms, and conform to these. I don’t think I’m stretching this too far. In what we call the developed Western world, we seek redemption and purification from the more extreme forms of our material indulgence: we fill our faces with drugs, drink, bad food and other indulgences, we know it’s wrong, and we crave ritualistic protection from the consequences, a public ‘transitional ritual’ commemorating our return to healthier behavioural norms.

This process of professionalising the obvious fosters a sense of mystery around science, and health advice, which is unnecessary and destructive. More than anything, more than the unnecessary ownership of the obvious, it is disempowering. All too often this spurious privatisation of common sense is happening in areas where we could be taking control, doing it ourselves, feeling our own potency and our ability to make sensible decisions; instead we are fostering our dependence on expensive outside systems and people.

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.

For perspective, there are only around 100,000,000,000,000,000,000,000,000,000,000 molecules of water in an Olympic-sized swimming pool. Imagine a sphere of water with a diameter of 150 million kilometres (the distance from the earth to the sun). It takes light eight minutes to travel that distance. Picture a sphere of water that size, with one molecule of a substance in it: that’s a 30C dilution.* At a homeopathic dilution of 200C (you can buy much higher dilutions from any homeopathic supplier) the treating substance is diluted more than the total number of atoms in the universe, and by an enormously huge margin. To look at it another way, the universe contains about 3 × 1080 cubic metres of storage space (ideal for starting a family): if it was filled with water, and one molecule of active ingredient, this would make for a rather paltry 55C dilution.

An even more extreme version of ‘regression to the mean’ is what Americans call the Sports Illustrated jinx. Whenever a sportsman appears on the cover of Sports Illustrated, goes the story, he is soon to fall from grace. But to get on the cover of the magazine you have to be at the absolute top of your game, one of the best sportsmen in the world; and to be the best in that week, you’re probably also having an unusual run of luck. Luck, or ‘noise’, generally passes, it ‘regresses to the mean’ by itself, as happens with throws of a die. If you fail to understand that, you start looking for another cause for that regression, and you find … the Sports Illustrated jinx.