Renata Micha, RD, PhD; Sarah K. Wallace, BA; Dariush Mozaffarian, MD, DrPH
Background—Meat consumption is inconsistently associated with development of coronary heart disease (CHD), stroke, and diabetes mellitus, limiting quantitative recommendations for consumption levels. Effects of meat intake on these different outcomes, as well as of red versus processed meat, may also vary.
Methods and Results—We performed a systematic review and meta-analysis of evidence for relationships of red (unprocessed), processed, and total meat consumption with incident CHD, stroke, and diabetes mellitus. We searched for any cohort study, case-control study, or randomized trial that assessed these exposures and outcomes in generally healthy adults. Of 1598 identified abstracts, 20 studies met inclusion criteria, including 17 prospective cohorts and 3 case-control studies. All data were abstracted independently in duplicate. Random-effects generalized least squares models for trend estimation were used to derive pooled dose-response estimates. The 20 studies included 1,218,380 individuals and 23 889 CHD, 2280 stroke, and 10 797 diabetes mellitus cases. Red meat intake was not associated with CHD (n_4 studies; relative risk per 100-g serving per day_1.00; 95% confidence interval, 0.81 to 1.23; P for heterogeneity_0.36) or diabetes mellitus (n_5; relative risk_1.16; 95% confidence interval, 0.92 to 1.46; P_0.25). Conversely, processed meat intake was associated with 42% higher risk of CHD (n_5; relative risk per 50-g serving per day_1.42; 95% confidence interval, 1.07 to 1.89; P_0.04) and 19% higher risk of diabetes mellitus (n_7; relative risk_1.19; 95% confidence interval, 1.11 to 1.27; P_0.001). Associations were intermediate for total meat intake. Consumption of red and processed meat were not associated with stroke, but only 3 studies evaluated these relationships.
Conclusions—Consumption of processed meats, but not red meats, is associated with higher incidence of CHD and diabetes mellitus. These results highlight the need for better understanding of potential mechanisms of effects and for particular focus on processed meats for dietary and policy recommendations.
(My Notes: This is speculative, but what other foods were consumed along with the “processed meats”? Pizza, subs, breads, chips, fries, soda’s……are these convenience “processed meats” all bad or is it the combination with sugars and refined carbs? Are these effects mitigated by a low carb diet in conjunction with minimally processed “processed meat”? Do they exist?)