Journalist Duped Millions Into Thinking Daily Chocolate Bars Aid Weight Loss. Here's Why.

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He even made a fake press release to announce the “study” findings. (Photo: Flickr/net_efekt)

“'Slim by Chocolate!’ the headlines screamed. A team of German researchers had found that people on a low-carb diet lost weight 10 percent faster if they ate a chocolate bar every day. It made the front page of Bild, Europe’s largest daily newspaper, just beneath their update about the Germanwings crash. From there, it ricocheted around the internet and beyond, making news in more than 20 countries and half a dozen languages. It was discussed on television news shows. It appeared in glossy print.”

So goes the lead paragraph to a confession, written by journalist John Bohannon for the website i09, that’s shaking up the media world.

Health stories sometimes get a bad rap for being sensational — drumming up hype around not-yet-proven claims, reporting the findings of small studies without really digging into the methodology, and overstating findings.

And all that was borne out when Bohannon conducted an experiment: He created a fake study showing chocolate can make you lose weight, adopted the erudite-sounding moniker of Johannes Bohannon, PhD to pose as the study author, got it published in a scientific journal, sent out a press release to tout the findings, and saw how many news publications would fall for it — because they didn’t ask the hard questions to find the truth about the so-called “study.”

And then he wrote about how easy it was to execute the research and slide it past fact-checkers. “I didn’t realize how big the problem was until our chocolate study made it into magazines and television news,” Bohannon tells Yahoo Health.

Here’s how it all began: After previously conducting research to see how many journals peer-reviewed paper submissions (sadly, less than half), Bohannon was approached by two German filmmakers working on a documentary about junk science in the diet industry. They wanted him to help pull together a study on people eating chocolate with a few thousand dollars, a few weeks, a German doctor to run the trial, and a statistician to work with the data. Bohannon accepted the challenge.

They used Facebook to recruit subjects, offering 150 euros to anyone willing to participate. Sixteen men and women between the ages of 19 and 67 showed up at the start of the study. The “researchers” separated them into three groups: a control group, a group following a low-carb diet, and a group following a low-carb diet plus a 1.5-ounce chocolate bar per day.

After participants followed the diet and stepped on the scale every day for three weeks, the study wrapped up with blood tests and a final weigh-in with questionnaires. Then, a financial analyst disappeared under a rock for a weekend, emerging with the claim.

The control group lost no weight on average, while the two low-carb diet groups lost roughly five pounds on average. The only difference? Those who noshed on the chocolate bars lost weight 10 percent faster, which was statistically significant.

Yes, this “finding” was based on actual data taken during the study. However, it was very flawed. Here’s why.

Related: That Glass of Red Wine May Not Be as Good For Your Health as You Think

Bohannon and his partners in crime measured 18 facets of health in 15 people (one study participant dropped out) — such as weight, cholesterol, sodium, blood protein levels, sleep quality, and so on. After playing with data across so many variables in such a small number of people, the team was bound to find something statistically significant. It could have easily been that chocolate improved sleep quality, or that chocolate lowered cholesterol. Here, it was that chocolate helps you lose weight faster.

From there, Bohannon probed “fake” journal publishers that don’t really do the whole peer-review thing to publish his study — and got multiple acceptances over the course of 24 hours. The team chose The International Archives of Medicine, was charged 600 euros, and saw the research go live within two weeks.

Bohannon crafted a press release on a bogus website for the “Institute of Diet and Health,” which he made up. The headline read, “Slim by Chocolate.” The coverage rolled in.

The study made the front page of Europe’s largest daily newspaper, Bild, and landed in the June issue of Shape magazine. and the Huffington Post covered it, and a reporter from Mens Health reached out about the study for the mag’s September issue, Bohannon said on io9.

Bohannon was quoted by publications, saying token researcher phrases like “The best part is you can buy chocolate everywhere,” and “When you eat chocolate on a diet, it’s a daily reward, so you don’t feel deprived.”

The lesson? We like to think of science as factual. However, it’s consciously and unconsciously manipulated, and frequently filters out to the public unchecked. As Bohannon points out, even serious, heavily funded research has trouble making real, legitimate claims about how to handle our health.

The best part of the fake study might have been the readers who piped in on the “results.” They probed. One asked why daily calorie measurements weren’t listed for anyone in the study, and another why the domain for Bohannon’s Institute of Diet and Health website was only set up in March.

To sort through the junk science, that’s the kind of discernment we all need. “Readers have to demand that diet and nutrition be treated like real science by journalists, just like astrophysics,” Bohannon says.

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