Objectives: To study total, processed, and unprocessed red meat in relation to risk of coronary heart disease (CHD) and to estimate the effects of substituting other protein sources for red meat with CHD risk.
Design: Prospective cohort study with repeated measures of diet and lifestyle factors.
Setting: Health Professionals Follow-Up Study cohort, United States, 1986-2016.
Participants: 43 272 men without cardiovascular disease or cancer at baseline.
Main outcome measures: The primary outcome was total CHD, comprised of acute non-fatal myocardial infarction or fatal CHD. Cox models were used to estimate hazard ratios and 95% confidence intervals across categories of red meat consumption. Substitution analyses were conducted by comparing coefficients for red meat and the alternative food in models, including red meat and alternative foods as continuous variables.
Results: During 1 023 872 person years of follow-up, 4456 incident CHD events were documented of which 1860 were fatal. After multivariate adjustment for dietary and non-dietary risk factors, total, unprocessed, and processed red meat intake were each associated with a modestly higher risk of CHD (hazard ratio for one serving per day increment: 1.12 (95% confidence interval 1.06 to 1.18) for total red meat, 1.11 (1.02 to 1.21) for unprocessed red meat, and 1.15 (1.06 to 1.25) for processed red meat). Compared with red meat, the intake of one serving per day of combined plant protein sources (nuts, legumes, and soy) was associated with a lower risk of CHD (0.86 (0.80 to 0.93) compared with total red meat, 0.87 (0.79 to 0.95) compared with unprocessed red meat, and 0.83 (0.76 to 0.91) compared with processed red meat). Substitutions of whole grains and dairy products for total red meat and eggs for processed red meat were also associated with lower CHD risk.
Conclusions: Substituting high quality plant foods such as legumes, nuts, or soy for red meat might reduce the risk of CHD. Substituting whole grains and dairy products for total red meat, and eggs for processed red meat, might also reduce this risk.
© Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.