October 8, 2019

An epidemiologist and lead researcher behind controversial guidelines about processed and red meat published last week had previous research ties to a major food industry group that he did not disclose, Tara Parker-Pope and Anahad O'Connor report for the New York Times.

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Background

The guidelines, published last week in the Annals of Internal Medicine, say there isn't convincing evidence that adults need to reduce their intake of processed and red meats to improve health, countering prominent dietary guidelines that for years have warned consumers to eat less of those foods.

The researchers found that the effects of cutting three servings of red meat resulted in seven fewer cancer-related deaths per 1,000 people. The researchers similarly said they found "very small absolute risk," or statistically insignificant differences, and weak evidence related to potential harms for many of the other outcomes measured.

The guidelines counter those from leading organizations, such as the U.S. Department of Agriculture and the World Health Organization (WHO), and were met with swift pushback from the American Cancer SocietyAmerican Heart Association, and the Harvard T.H. Chan School of Public Health.

However, Bradley Johnston, an epidemiologist at Dalhousie University who led the analysis, said the guidelines relied on the highest standard of scientific evidence. He noted that the researchers had reported no conflicts of interest and conducted the analysis without outside funding.

Researcher previously received payment from industry

Days after the guidelines were published, Parker-Pope and O'Connor reported that Johnston had previously done research for the International Life Sciences Institute (ILSI), an industry trade group whose members include McDonald's, Coca-Cola, and Cargill, which is one of the largest beef processors in North America, according to Parker-Pope and O'Connor. WHO and other organizations have previously accused ILSI of trying to disprove public health recommendations in the interest of its corporate members.

While Johnston and the other researchers in a disclosure form for the meat study said they had no conflicts of interest to report within the last three years, Johnston in 2016 was the senior author on a different study published in the Annals of Internal Medicine that tried to discredit international health guidelines that advised consumers to eat less sugar. That study was funded by ILSI.

Johnston says his previous work is irrelevant

Johnston in an interview with the Times said his previous work with ILSI is not related to and had no influence on his most recent research and the corresponding guidelines.

In fact, Johnston said that when the sugar study was published, he was open about his connection with ILSI and added that he regretted working on the ILSI-funded study. "That was a big lesson to separate oneself" from industry, Johnston said of the earlier paper. "It's not worth working with industry at all."

Further, Johnston said that he did not disclose his previous work with ILSI when the meat study was published because the disclosure form only asked about conflicts of interest within the last three years. Johnston said that while the ILSI-supported study was published in December 2016, the money from ILSI arrived in 2015, which he said means "it was outside of the three year period for disclosing competing interests."

Implications

Still, critics of the latest meat guidelines have noted Johnston failed to comply with "the spirit of financial disclosure," Parker-Pope and O'Connor write.

Marion Nestle, a professor of nutrition, food studies and public health at New York University, said, "It is always better to disclose fully, if for no other reason than to stay out of trouble when the undisclosed conflicts are exposed." She continued, "Behind the scenes, ILSI works diligently on behalf of the food industry. … Even if ILSI had nothing to do with the meat papers … the previous paper suggests that Johnston is making a career of tearing down conventional nutrition wisdom."

Christine Laine, editor in chief of the Annals of Internal Medicine, said the journal would've still published the study, even if Johnston had disclosed his potential financial conflict of interest. "I don't think we would have made a different decision about publishing the manuscript if he had that on his conflicts disclosure," Laine said.

In addition, Laine said people on both sides of the meat guidelines debate have conflicts they haven't acknowledged. For instance, she noted critics "do workshops on plant-based diets, do retreats on wellness, and write books on plant-based diets" (Parker-Pope/O'Connor, New York Times, 10/4).

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