Ben Goldacre is exasperated. He’s not exactly angry — that would be much less fun to read — except in certain circumstances. He is irked, vexed, bugged, ticked off at the sometimes inadvertent (because of stupidity) but more often deliberate deceptions perpetrated in the name of science. And he wants you, the reader, to share his feelings.

His initial targets are benign. Health spas and beauty salons offer detox footbaths for $30 and up, or you can buy your own machine online for $149.99. You put your feet in salt water through which an electrical charge runs. The water turns brown, the result of electrolysis, and you’re supposedly detoxed. Dr. Goldacre describes how one could produce the same effect with a Barbie doll, two nails, salt, warm water and a car battery charger, thus apparently detoxing Barbie. The method is dangerous, however, because of the chance of getting a nasty shock, and he wisely warns readers not to try his experiment themselves. As for homeopathy, he says that it may indeed work but it’s not because of the ingredients in those pills. You can pay for Valmont Cellular DNA Complex (made from “specially treated salmon roe DNA”), but Vaseline works just as well as a moisturizer.

There’s more here than just debunking nonsense. The appearance of “scienciness”: the diagrams and graphs, the experiments (where exactly was that study published?) that prove their efficacy are all superficially plausible, with enough of a “hassle barrier” to deter a closer look. Dr. Goldacre (a very boyish-looking 36-year-old British physician and author of the popular weekly “Bad Science” column in The Guardian) shows us why that closer look is necessary and how to do it.

You’ll get a good grounding in the importance of evidence-based medicine (the dearth of which is a “gaping” hole in our culture). You’ll learn how to weigh the results of competing trials using a funnel plot, the value of meta-analysis and the Cochrane Collaboration. He points out common methodological flaws: failure to blind the researchers to what is being tested and who is in a control group, misunderstanding randomization, ignoring the natural process of regression to the mean, the bias toward positive results in publication. “Studies show” is not good enough, he writes: “The plural of ‘anecdote’ is not data.”