The real issue around the red meat study is scientific credibility

Vet Advice with Dr. Ron Clarke

The real issue around the red meat study is scientific credibility

Dr. Bradley Johnston, an associate professor of community health and epidemiology at Dalhousie University, escalated the protein war when he published a report contradicting existing nutritional guidelines related to red meat consumption.

According to Johnston, “Most adults shouldn’t worry about how much red or processed meat they eat. This is not just another study of red and processed meat, but a series of high-quality systematic reviews resulting in recommendations we think are far more transparent, robust and reliable.”

The new guidelines were celebrated by the carnivores among us, and stoutly denounced as nutritional heresy by others. The recommendations — which conflict with virtually every other in existence, including the latest iteration of Canada’s Food Guide — are based on studies involving millions of people. The authors found lowering red or processed meat consumption had little, and often trivial, effects in reducing the absolute risk for cardiovascular disease, stroke, heart attack, cancer, diabetes or death from any cause.

Researchers at Dalhousie and McMaster universities led the panel of international scientists. On the basis of four systematic reviews (meta-analysis), they assessed the risks of red and processed meat.

The authors’ conclusion as reported in the Annals of Internal Medicine was that “individuals continue their current consumption of meat.”

Meta-analysis implies a quantitative, formal, epidemiological review and assessment of previous research studies as a cluster. Bottom line: Bradley’s team could not say with any certainty that eating red or processed meat causes cancer, diabetes or heart disease.

The study will stand as an antithesis to the vegan and animal rights activist crowds who push a simple “go vegan because we shouldn’t eat animals” message. Over the past two decades, more effort has been directed away from meat consumption citing its effect on human health.

Those in the industry have also been bombarded with other issues such as the environmental impact of meat consumption (climate emergency and the greenhouse gas emissions that come from animal farming) and animal welfare. By attacking meat, dairy, poultry and eggs from all angles, activist groups hoped to have consumers second-guess putting these products on their plates. Cultured meats and plant-based proteins are new tools in the war chest of activists aimed at dropping red meat from human diets.

The World Health Organization classified red and processed meats as cancer-causing. Public health bodies worldwide urge people to limit their intake of red and processed meat to reduce their cancer risk.

Yet the 14-member international team led by Johnston concluded that those who like meat should not stop on health grounds. “Based on the research, we cannot say with any certainty that eating red or processed meat causes health conditions previously described,” he said.

Many scientists agreed with the team that the evidence from studies around the world remained flawed. Some told The Guardian that existing evidence left them open to both interpretations — either that meat could cause health harm or that it did not.

The lead author of the EAT-Lancet Commission, representing 37 world-leading scientists from 16 countries covering various scientific disciplines, recommends a plant-based diet for both environmental sustainability and health. The group excoriated Johnston’s work.

The commission’s goal is to reach scientific consensus on defining targets for healthy diets and sustainable food production that will allow the world to feed up to 10 billion people by 2050.

Walter Willett, professor of epidemiology and nutrition at the Harvard TH Chan School of Public Health, said, “This report has layers of flaws and is the most egregious abuse of evidence that I have ever seen.”

Willett also advocates a plant-based diet.

The Dalhousie and McMaster study is good news from the perspective of beef and pork production and word that meat is okay is a reprieve from the many naysayers that come down hard on meat.

But veterinarians should look upon the Dalhousie and McMaster study with some trepidation. Veterinarians try hard to promote the value of a livestock industry we love. It grows more difficult among a growing field of skeptics. It seems we are now faced with the more serious questions of how could science be so wrong for so long, and where are the boundaries of scientific credibility?

Neil de Grasse Tyson, an astute American astrophysicist, author and science communicator, reminds the world about believing in science. Good science is true whether or not you believe in it. The real job of communicators is to provide the ability to understand so listeners can make the right decisions — what to believe, what not to believe. He goes on to remind us that when people in power stand in denial of science, these acts are tantamount to dismantling informed democracies.

The real truth about the confusing red meat study is complicated and it boils down to a simple fact: nutrition science is far harder than most people assume. The new study is actually more than one piece of research — researchers from across the world came together and conducted a series of systematic reviews of the evidence, looking at the effects of red meat on a wide variety of health issues. Their argument remains fairly simple: there is currently no good evidence that red meat is harmful to health. The most evidence-based guideline is not to tell people to eat either more or less red meat.

Research simply hasn’t proven whether red meat is harmful or not.

The results met with a predictable outcry from other scientists who have spent decades developing guidelines that say that red meat can be harmful, so eat less of it.

Why do these new studies contradict established research? The basic answer has more to do with interpretation than anything else.

About the author


Dr. Ron Clarke

Dr. Ron Clarke prepares this column on behalf of the Western Canadian Association of Bovine Practitioners. Suggestions for future articles can be sent to Canadian Cattlemen ([email protected]) or WCABP ([email protected]).

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