In a study that is bound to be controversial — and confusing for consumers who feel whipsawed by conflicting nutrition advice — researchers from seven countries have reported finding few health benefits associated with cutting back on red or processed meats.
The results appeared in five reports published in the Annals of Internal Medicine on Monday.
The research consortium, known as NutriRECS, anticipated the new reports and guidelines would rile the nutrition community, said Bradley Johnston, lead author and associate professor of epidemiology at Dalhousie University in Nova Scotia.
“Our findings are contrary to what they have been telling us for years,” Johnston said.
The recommendations were based on four systematic reviews of numerous observational studies that looked at meat consumption and health, and one review that looked at values and preferences regarding red meats, according to the authors.
What the researchers found suggest that there isn’t a strong enough connection between meat consumption and poor health outcomes to warrant changing most people’s habits, he said.
NutriRECS — comprised of scientists from around the world “unencumbered by institutional constraints and conflicts of interest,” according to its website — expected to find higher-quality evidence regarding the meat-health connection but didn’t, Johnston said.
The findings should not be taken as permission to pile on the beef and bacon. Rather, the fact that the team couldn’t find strong evidence concerning meat and health suggests that "you should engage in shared decision-making with family or physicians,” said Johnston. “The hope is that this will lead to more informed decision-making.”
Heart disease and cancer are among the health conditions frequently linked with meat consumption.
The data used in the reviews came from about 180 cohort studies that included millions of participants. For those who ate three fewer servings of meat per week, the reduced risk of cancer, diabetes, or heart disease that could be realized by that change was small, according to the study.
Among 54 studies that looked at meat consumption and health-related personal values, the authors found that people who choose to eat red or processed meat enjoyed it so much, they might be reluctant to change their diets.
In an editorial on the new guidelines also published in the journal, Aaron E. Carroll and Tiffany S. Doherty at the Indiana University School of Medicine stated it was “probably time for a major overhaul of the methods for communicating nutritional data in ways that might get through to target populations and change health outcomes.”
The two authors noted there are many reasons other than health to reduce meat consumption, including animal welfare and the environment. If those result in reductions of meat consumption and a small health beneﬁt as a side effect, then “everyone wins,” they wrote.
The authors did not consider animal welfare and environmental considerations when making their recommendations, Johnston said.
The study outcomes have already generated a strong response from top health organizations, including the American Institute for Cancer Research (AICR), as well as global research experts who are urging consumers to limit red meat to no more than three portions a week and to eat little or no processed meat to help prevent cancer.
The results of the new study were not that significantly different from what the widely accepted World Cancer Research Fund/AICR’s 2018 report had already found, but the confusing interpretation of the results has lead to an unnecessary recommendation to the public, the AICR stated in a news release.
The 12,000-member Physicians Committee for Responsible Medicine filed a petition Monday against the Annals of Internal Medicine over what it said are false claims and stated that the new guidelines are at odds with the data from the studies they used.
"It is a major disservice to public health,” Physicians Committee president Neal Barnard said in a statement. “These misrepresentations are directly at odds with abundant scientific evidence demonstrating the potential ill health effects of red and processed meat and the benefits of reducing consumption of red and processed meat.”
The group pointed to a recent study from the Harvard School of Public Health that found the risk of premature death rises by 12% on average with the addition of each daily serving of red meat. For processed meats the risk was 20%. Two other studies found that eating a diet high in red or processed meats increased the risks of colorectal cancers, they stated.
Susan Levin, director of nutrition education for the Physicians Committee for Responsible Medicine, said she found the new report “really disconcerting.” In her experience, adverse health risks go up the more meat you eat, she said.
“You have a crisis with people not understanding at all what is healthy or not,” she said. “No wonder we are completely confused about nutrition and health."
David Becker, a Temple Health cardiologist and Inquirer contributor, said it is difficult for him to reconcile past research with the new study. The underlying data, however, are not at question, he said.
“Nowhere does it say that red and processed meat is good for you, and that is what the conclusion implies,” he said. He pointed out the confusion that exists when experts keep changing dietary advice.
“I disagree with the recommendations, not the analysis,” Becker said. The recommendations will make it easier for people who do not want to take advice when it comes to diet, he said.