'Chocolate diet' study was deliberate hoax, exposed shoddy journalism - author

AFP Photo / Bertrand Guay
A sensational study about the impact of chocolate on weight loss, published by a medical journal and reported in half a dozen languages across over 20 countries, was a deliberate plot to expose bad science in diet studies, its author said.

Seductively titled “Slim by Chocolate,” the study claimed that people on a low-carb diet lost weight 10 percent faster if they ate a chocolate bar every day. It first appeared in a German tabloid Bild, and rapidly spread around the world.

However, there was never a “Johannes Bohannon, PhD” and the “Institute of Diet and Health” was a front. The hoax was the brainchild of two German filmmakers seeking to “reveal the corruption of the diet research-media complex by taking part,” wrote science reporter John Bohannon in a post on Gawker’s media blog io9.

German journalists Peter Onneken and Diana Loebl reached out to Bohannon, who actually has a doctorate in molecular biology, and had previously exposed the perils of publishing in fee-based open access academic journals. They set up an actual clinical trial in Germany with 15 subjects, designed to show that chocolate was good for something.

That study design is a recipe for false positives,” Bohannon wrote. “The results are meaningless, and the health claims that the media blasted out to millions of people around the world are utterly unfounded.”

They paid 600 Euros (approximately $650) to publish the study in the International Archives of Medicine.

Although the Archives’ editor claimed that “all articles submitted to the journal are reviewed in a rigorous way,” Bohannon wrote, his paper was published less than two weeks after the journal charged Onneken’s credit card – without changing a single word.

Following the publication of Bohannon’s confession, the journal appears to have removed the study from their website.

The next step was crafting a seductive press release, filled with carefully chosen buzzwords like “flavonoids” and “bioactive compounds” while carefully avoiding any specific claims aside from the vague notion chocolate was beneficial.

I felt a queazy [sic] mixture of pride and disgust as our lure zinged out into the world,” Bohannon wrote. From Bild, the story spread to other newspapers; the confessional showcases photos of the story at the Daily Mail, Daily Express, Shape, the Irish Examiner, Huffington Post, Modern Healthcare, and others.

The key is to exploit journalists’ incredible laziness,” he added. “If you lay out the information just right, you can shape the story that emerges in the media almost like you were writing those stories yourself. In fact, that’s literally what you’re doing, since many reporters just copied and pasted our text.”

Gary Schwitzer, publisher of the media watchdog Health News Review was not surprised to read about the hoax’s effectiveness.

Should we really be surprised to see journalists fooled by tricks … when we have journalists reporting on studies that never existed? When we have news releases from industry, academic medical centers and medical journals misleading journalists who then mislead the public?” he wrote at Retraction Watch.

The problem is much worse than a publishing prank that fools millions. It’s a credibility crisis for science and for journalism. And consumers at the end of the food chain will be – indeed, already are – poisoned.”

Bohannon did find a “glint of hope in this tragicomedy,” however. Many readers posted comments under the articles disputing the study’s legitimacy, methodology and results – questions, he says, the reporters should have asked, but did not.