Medical journal says red, processed meat OK, but advocates fight back
A prominent medical journal said Monday that there is not enough evidence to tell people to reduce consumption of red meats and processed meats, but a range of prominent nutrition advocates including the Center for Science in the Public Interest said they disagreed with the dietary advice.
“Dietary guideline recommendations require consideration of the certainty in the evidence, the magnitude of potential benefits and harms, and explicit consideration of people’s values and preferences,” the Nutritional Recommendations Consortium, a group of doctors and researchers, said in an article published in the Annals of Internal Medicine, published by the American College of Physicians.
“Contemporary dietary guidelines recommend limiting consumption of unprocessed red meat and processed meat” on the grounds that the products can cause cancer, the article said.
“These recommendations are, however, primarily based on observational studies that are at high risk for confounding and thus are limited in establishing causal inferences, nor do they report the absolute magnitude of any possible effects. Furthermore, the organizations that produce guidelines did not conduct or access rigorous systematic reviews of the evidence, were limited in addressing conflicts of interest, and did not explicitly address population values and preferences, raising questions regarding adherence to guideline standards for trustworthiness.”
Other nutrition experts told The Washington Post and National Public Radio they couldn’t understand the conclusions.
“I am outraged and bewildered,” nutrition scientist Christopher Gardner, a professor of medicine at Stanford University, told NPR.
“This is perplexing, given the … clear evidence for harm associated with high red meat intake,” added Frank Hu, the chair of the Department of Nutrition at the Harvard T.H. Chan School of Public Health.
Bonnie Liebman, the nutrition director of the Center for Science in the Public Interest, recommended that the public ignore this study.
Liebman said the analysis of studies conducted by the researchers in the Annals had reached a different conclusion than most health experts largely for two reasons.
“First, while most health authorities look at all of the evidence on meat, this panel looked only at observational studies and randomized trials,” Liebman said.
“For example, when the International Agency for Research on Cancer concluded that processed meat is a human carcinogen and red meat is a probable human carcinogen, IARC also considered what it called ‘strong mechanistic evidence,’ such as studies that find potential human carcinogens in the gut after people are fed red meat.
“Similarly, the American Heart Association and the American College of Cardiology also considered evidence from randomized trials showing that an overall healthy diet that is low in red meat can reduce LDL — or ‘bad’ — cholesterol, which are directly linked to the risk of heart attacks and stroke.
“Second, the authors of the new papers conclude that randomized controlled trials do not find a lower risk of disease in people who eat less meat. This conclusion was based almost exclusively on the Women’s Health Initiative, a trial that compared disease rates in women who were randomly assigned to eat either a lower-fat diet or their usual diets for eight years.
“However, the reported difference in meat intake was only about half an ounce — about one-fifth of a burger — per day, so it’s no surprise that the trial found no difference in cancer or heart disease risk.
“CSPI advises consumers to ignore these new recommendations and instead follow the advice of nearly all major health authorities to cut back on red and processed meats. That sensible advice, based on the best available data, can not only lower the risk of disease but can also help fight the climate crisis that poses a grave threat to the planet that our children and grandchildren will inherit.”