New York: A surprising new study challenged decades of nutrition advice and gave consumers the green light to eat more red and processed meat. But what the study didn’t say is that its lead author has past research ties to the meat and food industry.
The new report, published in the Annals of Internal Medicine, stunned scientists and public health officials because it contradicted long-standing nutrition guidelines about limiting consumption of red and processed meats. The analysis, led by Bradley C. Johnston, an epidemiologist at Dalhousie University in Canada, and more than a dozen researchers concluded that warnings linking meat consumption to heart disease and cancer are not backed by strong scientific evidence.
Several prominent nutrition scientists and health organisations criticised the study’s methods and findings. But Johnston and his colleagues defended the work, saying it relied on the highest standards of scientific evidence, and noted that the large team of investigators reported no conflicts of interest and conducted the review without outside funding.
Johnston also indicated on a disclosure form that he did not have any conflicts of interest to report during the past three years. But as recently as December 2016 he was the senior author on a similar study that tried to discredit international health guidelines advising people to eat less sugar. That study, which also appeared in the Annals of Internal Medicine, was paid for by the International Life Sciences Institute, or ILSI, an industry trade group largely supported by agribusiness, food and pharmaceutical companies and whose members have included McDonald’s, Coca-Cola, PepsiCo and Cargill, one of the largest beef processors in North America. The industry group, founded by a top Coca-Cola executive four decades ago, has long been accused by the World Health Organisation and others of trying to undermine public health recommendations to advance the interests of its corporate members.
In an interview, Johnston said his past relationship with ILSI had no influence on the current research on meat recommendations. He said he did not report his past relationship with ILSI because the disclosure form asked only about potential conflicts within the past three years. Although the ILSI-funded study publication falls within the three-year window, he said the money from ILSI arrived in 2015, and he was not required to report it for the meat study disclosure.
“That money was from 2015 so it was outside of the three-year period for disclosing competing interests,” Johnston said. “I have no relationship with them whatsoever.”
Critics of the meat study say that while Johnston may have technically complied with the letter of the disclosure rules, he did not comply with the spirit of financial disclosure.
“Journals require disclosure, and it is always better to disclose fully, if for no other reason than to stay out of trouble when the undisclosed conflicts are exposed,” said Marion Nestle, a professor of nutrition, food studies and public health at New York University who studies conflicts of interest in nutrition research. “Behind the scenes, ILSI works diligently on behalf of the food industry; it is a classic front group. Even if ILSI had nothing to do with the meat papers — and there is no evidence of which I am aware that it did — the previous paper suggests that Johnston is making a career of tearing down conventional nutrition wisdom.”
Johnston’s ties to the 2016 ILSI-funded sugar study show how ILSI has methodically cultivated allies in academia around the world, and how it recruits influential scientists to help shape global nutrition advice and counter what it perceives to be anti-food industry guidelines by health organisations.
When Johnston and his colleagues first published the sugar study, they said that ILSI had no direct role in conducting the research other than providing funding, but later amended their disclosure statement in the Annals after The Associated Press obtained emails showing that ILSI had “reviewed” and “approved” the study’s protocol.
Johnston said that when he published the sugar study in 2016, he put his connection with the food industry group “front and centre.” He said in hindsight he was “naive” when he agreed to work on the ILSI-funded study about sugar guidelines. It was during a conference call on the sugar study that he realised the extent that industry figures were involved with that organisation. He declined to say who was on the conference call.
“It wasn’t until I was on a conference call with them and people were introducing themselves where I realised this is not what I expected,” he said. “Then I saw the reaction from the paper we did publish, which I think was a very good paper. People didn’t get that message. They got stuck on the funding part. That was a big lesson to separate oneself. It’s not worth working with industry at all.”
Dr Christine Laine, editor-in-chief of the Annals of Internal Medicine, said the medical journal asks people to disclose their financial interests but relies on the integrity of the researcher and does not attempt to verify the forms. “We are really leaving it to the authors to disclose,” Laine said. “We advise authors if they wonder ‘Should I disclose this or not,’ they should err on the side of disclosure.”
Laine noted that people on both sides of the meat issue have conflicts of interest. “Many of the people who are criticising these articles have lots of conflicts of interest they aren’t talking about,” she said. “They do workshops on plant-based diets, do retreats on wellness and write books on plant-based diets. There are conflicts on both sides.”
Laine said if Johnston had chosen to disclose a financial relationship with the food industry group, it would not have changed the journal’s decision to publish the research. What matters to the journal editors and peer-review team, she said, is the fact that the group had clear protocols for examining the data and was transparent about its methods.
“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. “We certainly know that in the past he did nutrition research that was funded by industry. It’s a judgement call if that should be disclosed. I think at some level that’s a little bit of noise around this. The methods of what these researchers did and their conclusions are out there, and people can disagree with that.”
Critics of the meat study say that it has similarities to the industry-funded sugar study and uses the same standard to evaluate evidence. Dr Frank Hu, the chair of the nutrition department at the Harvard T.H. Chan School of Public Health, said he was stunned when he realised that Johnston was both the leader of the meat study and the same researcher who led the industry-funded review that attacked guidelines advising people to eat less sugar. He said that in both cases Johnston undercut sugar and meat recommendations by using a tool called GRADE that was mainly designed to rate clinical drug trials, not dietary studies.
“You can’t do a double-blinded placebo-controlled trial of red meat and other foods on heart attacks or cancer,” Hu said. “For dietary and lifestyle factors, it’s impossible to use the same standards for drug trials.”
Drug trials are primarily designed to look at efficacy and safety, Hu said, while the main goal of diet studies is to identify risk factors that influence obesity and chronic diseases. That is why scientists use data from large observational studies and randomised trials to look at the health effects of different eating patterns and other behaviours that cannot be studied like pharmaceutical therapies.
Johnston said the real problem is that people don’t want to accept findings that contradict long-held views. “People have very strong opinions,” he said. “Scientists should have intellectual curiosity and be open to challenges to their data. Science is about debate, not about digging your heels in.”