In the JournalsPerspective

No need for adults to eat less red meat, new guidelines say

Photo of Bradley C. Johnston
Bradley C. Johnston

Most people do not need to reduce the amount of red and processed meat that they eat, according to new guidelines published in the Annals of Internal Medicine. The recommendations run contrary to previous findings.

“Based on four systematic reviews assessing the potential harms associated with red and processed meat consumption, and one systematic review assessing people’s health-related values and preferences on meat consumption, we made a weak recommendation that most people need not reduce their red meat and processed meat,” Bradley C. Johnston, PhD, associate professor in the department of community health and epidemiology at Dalhousie University in Halifax, Nova Scotia, Canada, told Healio Primary Care.

The new guideline comes despite findings that red and processed meat consumption was associated with cancer risk, fatty liver disease, cardiovascular disease and other health issues.

Investigators followed the Nutritional Recommendations guideline development process — which engages rigorous methodology for systematic reviews and uses GRADE to rate certainty of evidence for every outcome — to create the new guidelines. They conducted a literature review of studies that specifically evaluated red and processed meat intake and those that examined dietary patterns with varied meat consumption. After reviewing the evidence, a panel with 14 members from seven countries voted to make the final recommendations.

Image of red meat in store 
Most people do not need to reduce the amount of red and processed meat that they eat, according to new guidelines published in the Annals of Internal Medicine. The recommendations run contrary to previous findings.
Source: Adobe Stock

Researchers found low- to very low-certainty evidence from 12 randomized control trials with 54,000 participants that a diet with minimal red and processed meat intake may have little or no effect on cardiometabolic health and cancer mortality or incidence.

An analysis of cohort studies also revealed low-certainty evidence that decreasing red meat consumption could result in slightly reduced risks for certain cardiovascular outcomes and lifetime cancer mortality, with no significant differences in the risk for other cancer outcomes or cardiovascular mortality.

For processed meat, cohort studies involving 3.5 million patients identified low- to very low-certainty evidence that eating less processed meat was tied to a very small reduced risk for certain cardiometabolic outcomes and lifetime cancer mortality, with no significant difference in CVD or other cancer outcomes.

Researchers noted that they made these recommendations in part because the slightly reduced health risks associated with decreased red and processed meat consumption would not be enough motivation for people to change their eating habits.

“There is only low certainty evidence of a very small reduction in cancer or other adverse health consequences from reducing meat consumption,” Johnston said. “For most people who enjoy eating meat, the uncertain health benefits of cutting down are unlikely to be worth it.” – by Erin Michael

Disclosures: Johnston reports no relevant financial disclosures. Please see guideline for all other authors’ relevant financial disclosures.

Photo of Bradley C. Johnston
Bradley C. Johnston

Most people do not need to reduce the amount of red and processed meat that they eat, according to new guidelines published in the Annals of Internal Medicine. The recommendations run contrary to previous findings.

“Based on four systematic reviews assessing the potential harms associated with red and processed meat consumption, and one systematic review assessing people’s health-related values and preferences on meat consumption, we made a weak recommendation that most people need not reduce their red meat and processed meat,” Bradley C. Johnston, PhD, associate professor in the department of community health and epidemiology at Dalhousie University in Halifax, Nova Scotia, Canada, told Healio Primary Care.

The new guideline comes despite findings that red and processed meat consumption was associated with cancer risk, fatty liver disease, cardiovascular disease and other health issues.

Investigators followed the Nutritional Recommendations guideline development process — which engages rigorous methodology for systematic reviews and uses GRADE to rate certainty of evidence for every outcome — to create the new guidelines. They conducted a literature review of studies that specifically evaluated red and processed meat intake and those that examined dietary patterns with varied meat consumption. After reviewing the evidence, a panel with 14 members from seven countries voted to make the final recommendations.

Image of red meat in store 
Most people do not need to reduce the amount of red and processed meat that they eat, according to new guidelines published in the Annals of Internal Medicine. The recommendations run contrary to previous findings.
Source: Adobe Stock

Researchers found low- to very low-certainty evidence from 12 randomized control trials with 54,000 participants that a diet with minimal red and processed meat intake may have little or no effect on cardiometabolic health and cancer mortality or incidence.

An analysis of cohort studies also revealed low-certainty evidence that decreasing red meat consumption could result in slightly reduced risks for certain cardiovascular outcomes and lifetime cancer mortality, with no significant differences in the risk for other cancer outcomes or cardiovascular mortality.

For processed meat, cohort studies involving 3.5 million patients identified low- to very low-certainty evidence that eating less processed meat was tied to a very small reduced risk for certain cardiometabolic outcomes and lifetime cancer mortality, with no significant difference in CVD or other cancer outcomes.

Researchers noted that they made these recommendations in part because the slightly reduced health risks associated with decreased red and processed meat consumption would not be enough motivation for people to change their eating habits.

“There is only low certainty evidence of a very small reduction in cancer or other adverse health consequences from reducing meat consumption,” Johnston said. “For most people who enjoy eating meat, the uncertain health benefits of cutting down are unlikely to be worth it.” – by Erin Michael

Disclosures: Johnston reports no relevant financial disclosures. Please see guideline for all other authors’ relevant financial disclosures.

    Perspective
    Elizabeth Klodas

    Elizabeth Klodas

    This conclusion was based on the studies the panel chose to analyze and there were significant problems here.

    For example, one of the pivotal analyses of cardiac risk involved looking at randomized controlled trials of which there are few in nutrition research. By default, this meant that much of the data came from one study, the Women’s Health Initiative Dietary Modification trial. This trial was not designed as a more meat vs. less meat trial. Rather it was usual diet vs. lower fat intake. Yes, the women in the lower fat arm consumed approximately 1.4 servings less meat per week, but this represented a mere 20% reduction in meat intake and what was substituted in was not analyzed. If the substitution was low-fat processed carbohydrates, for example, a lack of significant outcome advantage would not be surprising.

    In addition, eating slightly less of a bad thing might not result in a divergence of outcome curves for decades and the average follow-up of the studies evaluated was closer to 10 years. A good analogy would be evaluating the health outcomes, over a decade, of smoking two packs per day vs. one and one-fifth packs per day and finding relatively little difference.  And then, because people enjoy smoking and have a hard time quitting, concluding that everyone might as well smoke two packs.

    Finally, I take issue with the premise that people don’t want to change their eating habits or that small changes don’t matter. People are willing to change if the new option fits their lives. Plant-based burgers are taking off because people like burgers even if they’re not made with meat. And we’ve shown by randomized controlled clinical trial in a free-living population that through an exchange of two small food servings a day, significant and rapid health improvements are attainable.   

    What’s most distressing is that these recommendations fly in the face of what we can readily observe. There are communities of people around the globe who experience exceptional healthy longevity, where being a centenarian is not unusual and where people experience 80% less heart disease, 75% less cancer and two-thirds less dementia. What do these people eat? A whole food plant-based diet. Meat consumption is celebratory and processed meat is rare. There’s certainly more to it that low red meat and processed meat consumption but whatever those people are doing, I’m doing that! And telling my patients to do the same.

    • Elizabeth Klodas, MD, FACC
    • Cardiologist
      Founder of Step One Foods

    Disclosures: Klodas reports no relevant financial disclosures.

    Perspective
    Leonard H. Calabrese

    Leonard H. Calabrese

    I am profoundly disappointed in these guidelines, both in terms of content and design. I feel sorry for people who work in the world of nutritional science, for I think that the ultimate goal they have is to elucidate the highest level of scientific data on diet and nutrition, which can be utilized to promote health and wellness I give them that. The way these data are disseminated is highly problematic. It confuses and frustrates the public, and that this will be a disservice to patients who seek to enhance their wellness behaviors. The reason I think this is that you can’t take diet, as one of our behaviors, and treat it like people are taking pills — do you want to eat meat, or do you not want to eat meat? Do you want to eat an egg, or do you not want to eat an egg? Do you want to drink dairy, or do you not want to drink dairy? Do you want to eat vegetables, nuts, etc.? People need to adopt diets that are known to be healthy based on strong science, I give them that, but not one food stuff at a time.

    I believe that meat is fine to eat if three-quarters of your plate is plant-based and one quarter of you plate is high quality meat, preferably grass fed I would encourage people to continue that. But to say “Oh, I’m going to now eat meat,” I want to know what’s on the rest of the plates. Is it full of french fries, or is it brussels sprouts and beans? I just don’t know how people can interpret these data in any type of responsible way. My goal in talking to patients, individually and in groups, is to have them adopt a diet with a prudent overall strategy — whether it be Mediterranean, vegan, paleo, or a combination of paleo and vegan — it’s not incriminating anybody for eating any one individual food.

    The last thing I’ll add is that people wrestle over whether they can eat an egg, or whether they can have a cookie, or whether they can have something that’s refined, stripped carbohydrates. People need to be empowered to recognize what they’re eating for their daily nutrition, health and wellness, and what they’re eating for entertainment. You can eat whatever you want for entertainment, but you need to have a plan that is prudent and doable for eating.

    Just cranking something out, saying it’s ok to eat meat — what does that tell anybody? I feel sorry for the people that work in this field, I mean, they’re good scientists, they’re trying to interpret these data, but it’s not one thing at a time — we eat holistically.

    • Leonard H. Calabrese, DO
    • Director
      RJ Fasenmyer Center for Clinical Immunology
      Cleveland Clinic
      Chief Medical Editor
      Healio Rheumatology

    Disclosures: Calabrese reports no relevant financial disclosures

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