Red Meat: Does It Cause Heart Disease, Type 2 Diabetes, and Cancer?

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Recent high-quality reviews of red meat and health outcomes, including Type 2 diabetes, heart disease and cancer:

  1. Processed meat intake and chronic disease morbidity and mortality: An overview of systematic reviews and meta-analyses (Using GRADE systematic review methodology)
    PLoS One 2019
    Conclusion: β€œOverall, the quality assessments of primary studies of the reviews are generally lacking; the scientific quality of the systematic reviews reporting positive associations between processed meat intake and risk of various cancers, T2D and CVD is moderate, and the results from case-control studies suggest more often a positive association than the results from cohort studies. The overall certainty in the evidence was very low across all individual outcomes, due to serious risk of bias and imprecision.”

By the Nutrirecs Team:

2. Red and Processed Meat Consumption and Risk for All-Cause Mortality and Cardiometabolic Outcomes: A Systematic Review and Meta-analysis of Cohort Studies (Using GRADE systematic review methodology)
Annals of Internal Medicine, 2019
Conclusion: β€œThe magnitude of association between red and processed meat consumption and all-cause mortality and adverse cardiometabolic outcomes is very small, and the evidence is of low certainty.”

3. Reduction of Red and Processed Meat Intake and Cancer Mortality and Incidence: A Systematic Review and Meta-analysis of Cohort Studies (Using GRADE systematic review methodology)
Annals of Internal Medicine, 2019
Conclusion: β€œThe possible absolute effects of red and processed meat consumption on cancer mortality and incidence are very small, and the certainty of evidence is low to very low.”

4. Effect of Lower Versus Higher Red Meat Intake on Cardiometabolic and Cancer Outcomes: A Systematic Review of Randomized Trials (Using GRADE systematic review methodology)
Annals of Internal Medicine, 2019
Conclusion: β€œLow- to very-low-certainty evidence suggests that diets restricted in red meat may have little or no effect on major cardiometabolic outcomes and cancer mortality and incidence.”

5. Patterns of Red and Processed Meat Consumption and Risk for Cardiometabolic and Cancer Outcomes: A Systematic Review and Meta-analysis of Cohort Studies (Using GRADE Guideline methodology)
Annals of Internal Medicine, 2019
Conclusion: β€œLow- or very-low-certainty evidence suggests that dietary patterns with less red and processed meat intake may result in very small reductions in adverse cardiometabolic and cancer outcomes.’

Nutrirecs Guideline Recommendation

Unprocessed Red Meat and Processed Meat Consumption: Dietary Guideline Recommendations From the Nutritional Recommendations (NutriRECS) Consortium (Using GRADE Guideline methodology) This paper summarizes and creates a guidelines recommendation from the four papers above.
Annals of Internal Medicine, 2019
Recommendation: The panel suggests that adults continue current unprocessed red meat consumption (weak recommendation, low-certainty evidence). Similarly, the panel suggests adults continue current processed meat consumption (weak recommendation, low-certainty evidence).

The original statement from WHO/IARC on red meat and cancer

Carcinogenity of consumption of red and processed meat
The Lancet
IARC (WHO) committee

Some challenges to this view:

A False Alarm on Red Meat and Cancer
The Financial Times (2015)
Gordon Guyatt, Distinguished Professor, Department of Clinical Epidemiology & Biostatistics, McMaster University.

Meat Is Linked to Higher Cancer Risk, W.H.O. Report Finds
The New York Times (2015)
Anahad O’Connor, reporter.

Know Your Risks, but Meat Still Isn’t the Enemy
The New York Times (2015)
Aaron E. Carroll, MD, MS is a Professor of Pediatrics, Associate Dean for Research Mentoring at Indiana University School of Medicine.