Key clinical point: A panel of experts has concluded that people should continue their current red meat or processed meat consumption based on available evidence.
Major finding: The harmful effects of red meat or processed meat consumption with regard to adverse cardiovascular outcomes, risk of type 2 diabetes, all-cause mortality, and incidence of cancer is based on a low to very-low certainty of evidence.
Study details: A guideline with recommendations based on four systematic reviews examining available evidence for red meat and processed meat consumption, and one systematic review of health-related values and preferences for consumption of meat.
Disclosures: Dr. El Dib reported receiving funding from the São Paulo Research Foundation, the National Council for Scientific and Technological Development, and the faculty of medicine at Dalhousie University. Dr. de Souza reports relationships with the Canadian Institutes of Health Research/Health Canada, McMaster Children’s Hospital, the Canadian Foundation for Dietetic Research and the World Health Organization in the forms of personal fees, grants, and speakers bureau and board of directorship appointments. Dr. Patel reports receiving grants and person fees from the National Institutes of Health, Sanofi, the National Science Foundation, XY.health, doc.ai, Janssen, and the CDC.
Johnston BC et al. Ann Intern Med. 2019 Oct 1. doi: 10.7326/M19-1621.
The new guidelines for red meat and processed meat consumption will be controversial. Since it is based on a review of all available data on red meat and processed meat consumption; however, it will be difficult to find evidence to argue against it, wrote Aaron E. Carroll, MD, MS; and Tiffany S. Doherty, PhD, in a related editorial.
Further, many participants in a systematic review by Valli and colleagues expressed beliefs that they had already reduced their meat consumption. Additionally, some cited mistrust of the information presented by studies as their explanation for not reducing meat consumption, according to Dr. Carroll and Dr. Doherty (Ann Intern Med. 2019 Oct 1. doi: 10.7326/M19-2620). “It’s not even clear that those who disbelieve what they hear about meat are wrong,” they added. “We have saturated the market with warnings about the dangers of red meat. It would be hard to find someone who doesn’t ‘know’ that experts think we should all eat less. Continuing to broadcast that fact, with more and more shaky studies touting potential small relative risks, is not changing anyone’s mind.”
Dr. Carroll and Dr. Doherty proposed that more study in this area with smaller cohorts may be of limited value, and randomized trials should be conducted in areas where we “don’t already know” the information.
The authors also called for efforts to be made to discuss reasons to reduce meat consumption unrelated to health.
“Ethical concerns about animal welfare can be important, as can concerns about the effects of meat consumption on the environment,” they concluded. “Both of these issues might be more likely to sway people, and they have the added benefit of empirical evidence behind them. And if they result in reducing meat consumption, and some receive a small health benefit as a side effect, everyone wins.”
Dr. Carroll and Dr. Doherty are from the Center for Pediatric and Adolescent Comparative Effectiveness Research, Indiana University, Indianapolis. These comments reflect their editorial in response to Johnston et al. Dr. Carroll reports receiving royalties for a book he wrote on nutrition; Dr. Doherty reports no relevant conflicts of interest.