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 this week in the Annals of Internal Medicine, stunned scientists and public health officials because it contradicted longstanding 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 organizations criticized the study’s methods and findings. But Dr. 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.
Dr. 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 Organization and others of trying to undermine public health recommendations to advance the interests of its corporate members.
In an interview, Dr. 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,” said Dr. Johnston. “I have no relationship with them whatsoever.”
Critics of the meat study say that while Dr. 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.”
Notably, Dr. Johnston and colleagues thought it was important to fully disclose their personal eating habits. The meat paper includes an appendix titled “Summary of Panelists’ Potential Conflicts of Interest,” that discloses whether each author eats red or processed meat and how often. Johnston reported no financial conflicts of interest but disclosed that he eats one to two servings of red or processed meat per week.
“We think that’s a potential bias that is worth disclosing,” said Dr. Johnston about the researchers’ personal eating habits.
Dr. 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 organizations.
When Dr. 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.
Dr. Johnston said that when he published the sugar study in 2016, he put his connection with the food industry group “front and center.” He said in hindsight he was “naïve” 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 realized the extent that industry figures were involved with that organization. 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 realized 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,” said Dr. Laine. “We advise authors if they wonder ‘Should I disclose this or not,’ they should err on the side of disclosure.”
Dr. Laine noted that people on both sides of the meat issue have conflicts of interest. “Many of the people who are criticizing 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.”
Dr. Laine said if Dr. 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,” said Dr. Laine. “We certainly know that in the past he did nutrition research that was funded by industry. It’s a judgment 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.”
Dr. Gordon Guyatt, chair of the 14-member panel that reviewed the analysis, said he is confident that the work was not in any way influenced by industry.
“Perhaps Brad was a little naïve, and both I and perhaps Christine Laine were a little negligent in it not occurring to us that he should probably declare the previous money he got from the previous project,” said Dr. Guyatt, an internal medicine physician and a distinguished professor at McMaster University. “All of that being said, I feel personally extremely comfortable that it had no effect on what we did.”
Dr. Guyatt noted that for 20 years he has been a pescatarian who eats only fish and no other meat. “Before I was involved in these systematic reviews and looking carefully at evidence, I had three reasons for not eating meat — animal welfare, the environment and health. Now I only have two reasons for not eating meat.”
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 realized that Dr. 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 Dr. 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,” Dr. 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, Dr. 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 randomized trials to look at the health effects of different eating patterns and other behaviors that cannot be studied like pharmaceutical therapies.
Dr. 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.”
But Dr. Hu said Dr. Johnston’s methods were not very objective or rigorous and the tool he employed in his meat and sugar studies could be misused to discredit all sorts of well-established public health warnings, like the link between secondhand smoke and heart disease, air pollution and health problems, physical inactivity and chronic disease, and trans fats and heart disease.
“Some people may be wondering what his next target will be,” Dr. Hu said. “But I’m concerned about the damage that has already been done to public health recommendations.”
