Hamilton

Hamilton professor calls criticism of his red meat study 'hysterical' and 'extreme'

A renowned Canadian doctor and researcher whose work challenges well-worn advice to limit meat consumption is dismissing mounting criticism as "over the top" and "hysterical."

The Physicians Committee for Responsible Medicine is asking for a retraction

This September 2017 photo shows ribeye steaks with thyme-garlic butter in New York. (Sarah Crowder/Associated Press)

A renowned Canadian doctor and researcher whose work challenges well-worn advice to limit meat consumption is dismissing mounting criticism as "over the top" and "hysterical."

Gordon Guyatt says he knew the series of papers he and his colleagues published in the Annals of Internal Medicine this week would elicit blowback.

But he did not expect anything like the widespread torrent of condemnation that continues to stream forth, among them letters to the editor excoriating the methodology and a petition by a Washington-based doctors' group to retract the work because it allegedly "promotes physical harm to those who follow its dangerous advice."  

"It's completely predictable and they're doing themselves no favours from my point of view about these sort of hysterical statements about: It shouldn't be published, let's keep it out of public view, let's not have scientific discourse operate as it should operate," says Guyatt, a celebrated professor and researcher at Hamilton's McMaster University who supervised a team of global researchers.

"It's hysterical. It's a hysterical response."

Guyatt, who supervised a research group with a panel of 14 members from seven countries, says the analyses sought to gauge the potential health impact of giving up burgers and sausage — how much cancer risk could be reduced by eating less meat?
McMaster University professor Gordon Guyatt. (McMaster University)

At the same time, researchers assessed the quality of the evidence used in previous dietary studies using an evaluative system known as GRADE, and tried to assess how inclined most people actually were to forsake steak for their health.

They've taken a pretty extreme stance and pushed very hard. And that's been going on for a long time.​​​​- Professor Gordon Guyatt, McMaster University

Their findings: evidence that links red meat consumption to cancer, heart disease and other bad health outcomes is weak, and if there is a benefit to giving up meat products, it's small. That's how they interpreted previously reported data that a reduction of three servings per week offered seven fewer cancer deaths per 1,000 people.

Given that the increased risks are slight and uncertain, cutting back wouldn't be worth it for people who really enjoy meat, concludes Guyatt, named Canada's Health Researcher of the Year in 2013.

"What we are saying is: This is a value and preference-sensitive decision," he explains of the work, co-led by Bradley Johnston, an associate professor at Halifax's Dalhousie University.

"So far, nobody has cared about the downside of quality of life reduction associated with decreasing or stopping eating meat."

Guyatt's analysis is too narrow, critic says

Still, critics including Dr. David Jenkins, professor of Nutritional Sciences and Medicine at the University of Toronto, chastise the work for being too narrow.

"We don't live in a vacuum with nothing else happening," says Jenkins.

"They're fine to be skeptics and that's healthy but ... it's not only nutritional science that people want to have weighed in the balance — we've also got things like climate change, we've got things like environmental destruction, we've got things like basically humane treatment of animals."

Jenkins fears the work could further confuse the general public and other health professionals, taking special issue with the publication's headline that declared: "New guidelines: No need to reduce red or processed meat consumption for good health."

Jenkins was among a group of scientists who pressed the Annals of Internal Medicine to postpone Monday's publication pending further review, deeming the headline inaccurate and "a major disservice to public health."

The Physicians Committee for Responsible Medicine, which includes 184 Canadian physician members, also sent a federal petition to the U.S. Federal Trade Commission asking for a retraction, saying false claims in the review "would discourage individuals from avoiding meat and from replacing meat with more healthful food choices, putting them at risk for major health problems."

"All I'm saying is: if somebody says there's a weak chance that if you walk across the street, you'll get shot, I would rather stay on the opposite side of the street," says Jenkins.

"The evidence against us giving up meat may be weak, but it's there. And the evidence for us eating more meat is not there."

Despite an avalanche of press coverage and conversation, the studies did not appear to change recommendations on healthy and balanced eating.

If anything, they appeared to entrench them further, with Health Canada and the Dieticians of Canada holding firm on their advice to favour plant-based proteins.

Debates between scientists can confuse the public, dietician says 

Kate Comeau of the Dietitians of Canada says food debates between scientists can be confusing for the public, especially because nutrition studies can rarely be conclusive when it's impossible to measure the effects of any single item.

"My hope would be that Canadians don't lose hope or lose trust in science. Science is so important to our understanding of health and how our bodies work," says Comeau.

"What's so exciting about being in 2019 is that we're seeing a lot of this debate happen — scientists are talking on Twitter and we can all watch ΓǪ That's exciting but it can also be confusing," she adds.

"What this study was showing was that the reality is, it's really hard to have strong evidence."

Guyatt's analysis doesn't suggest red meat or processed meats are healthy or that people should eat more of them, but Guyatt also doesn't discount the possibility that people who eat a lot of meat are in good health.

"I'm sure there are millions, tens of millions, hundreds of millions of people who eat a lot of meat who are in good health," he says.

Still, he says there needs to be greater acceptance that there is a lot of uncertainty in life, and that on some issues, definitive conclusions cannot be drawn.

"They've taken a pretty extreme stance and pushed very hard. And that's been going on for a long time," says Guyatt, referring to those who oppose meat.

"When that is fundamentally challenged, it is very threatening. And when it is challenged by credible academics with compelling evidence on which to challenge it, that intensifies the threat."

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