As Mark Thomas acknowledges at the beginning of this characteristically amusing and provocative jeremiad, he could have picked a more vulnerable target. We join the comedian-activist near the start of his global pursuit of Coca-Cola, in Atlanta airport, where he is passing time between visiting Coca-Cola's ghastly-sounding museum and venturing to understand the reality of its production in Colombia.

“Coca-Cola,” he reflects, “is the biggest brand in the world. [It has] a greater global reach than a flu virus [and] lawyers who excrete spare IQ points, and I am a dad sitting in an airport holding a teddy bear and an asthma inhaler muttering ‘Oh God, what have I done'.” Thomas is being somewhat ingenuous. By far the most entertaining left-wing polemicist currently operating, as well as one of the smartest and most effective, Thomas does not so much slay Goliaths as infest their loincloths with itching powder. His first book, As Used on the Famous Nelson Mandela, was an astonishing romp through the moral swamp of the global arms trade that would have been one of the funniest things ever written were it not all true. Belching Out The Devil maintains that standard.

At the core of Thomas's indictment is that Coca-Cola doesn't make much fizzy drink itself: it franchises production to companies around the world (the cokefacts.com website claims that “we bring refreshment to people in over 200 countries”). Not all these countries, inevitably, are known for stringent adherence to environmental standards or regard for human rights. Coca-Cola resembles, in these devolved relationships, the definition of “corporation” in Ambrose Bierce's The Devil's Dictionary: “An ingenious device for securing individual profit without individual responsibility.”

Thomas ventures repeatedly to the sharp end, to Turkey, Mexico, El Salvador and India, seeking the people affected, gathering the telling facts. Yet he never descends into self-righteous, Michael Moore-ish hectoring - if he doesn't know something, he says so, if his rival has a point, he concedes it, and he maintains an enviable strike rate of comic descriptions (Delhi traffic is “like playing Grand Theft Auto with four million people connected to the same console”).

Thomas will not stop people drinking Coca-Cola (it does, after all, taste pretty good). But he might prompt wider contemplation of the process by which Coca-Cola - and, by extension, every other branded product - gets into our hearts, minds, homes and stomachs. This is great comedy, great travel writing, and great reporting.

Belching Out the Devil: Global Adventures with Coca-Cola by Mark Thomas
Ebury, £11.99; 384pp Buy the book

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