Did Scientists Really Claim That Eating Chocolate Can Help You Lose Weight?


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Earlier this year, a team of German researchers revealed how people who ate dark chocolate while dieting lost more weight. The study, published in the journal called 'International Archives of Medicine', received instantaneous and jubilant media coverage.

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The study claimed that not only does chocolate accelerate weight loss, but it leads to healthier cholesterol levels and overall increased well-being. It appeared on the front page of Bild, Europe's largest daily newspaper, just beneath their update about the Germanwings crash.

Moreover, it made news in more than 20 countries where it was discussed on television news shows and appeared in glossy prints.

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It was unbelievable news. In other words, it was a hoax.

It turns out that the Institute of Diet and Health is just a Web site with no institute attached. Johannes Bohannon, health researcher and lead author of the study, is really John Bohannon, a science journalist. And the study, while based on real results of an actual clinical trial, wasn’t aimed at testing the health benefits of chocolate. It was aimed at testing health reporters, to see if they could distinguish a bad science story from a good one.

In many cases, they couldn’t.

Bohannon, who revealed the stunt in an essay for the io9 Web site on Wednesday, was part of a team of gonzo journalists and one doctor who, in Bohannon’s words, wanted to “demonstrate just how easy it is to turn bad science into the big headlines behind diet fads.”

It started last December when Bohannon was approached by a duo making a documentary about junk science and the diet industry

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They had also recruited a general practitioner and a statistician to help them set this up. Then the study began: In January, 16 subjects were randomly assigned to one of three groups: one consumed a low-carb diet, another enjoyed a low-carb diet and a daily 1.5-ounce bar of dark chocolate (81 percent cocoa content, if you’re curious), and the control group ate whatever they normally eat. The team analyzed 18 measurements ranging from cholesterol to sleep quality.

Turns out, the chocolate group lost weight 10 percent faster. And that’s great news if you don’t look too closely at the details. The paper, “Chocolate with high cocoa content as a weight-loss accelerator,” was accepted by multiple journals within a day of submission, and it only cost 600 Euros to publish.

Bohannon told the Washington Post that he didn't have any ethical qualms about tricking his fellow journalists this way

“I didn’t lie to reporters, except about my name. And whenever they asked me a scientific question about the study, I gave them a completely honest answer,” he said. “The whole point is that this was as bad as a lot of science that is considered ‘real’ science. It gets reported without people asking the right questions.”

However, not everyone agrees with Bohannon

“Going out of their way to court media coverage (that was going to repeat the story but never, ever follow up on the hoax once it was revealed — and this is a hoax) was ethically problematic,” one commenter wrote on Bohannon’s io9 essay. “If you want to uncover the shady workings, that didn’t really help. It seems like only the people who were already aware of the problems are going to be reached by this reveal.”


“Scientists say eating chocolate can help you lose weight,”

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