A Mediterranean-style eating pattern with lean, unprocessed red meat has cardiometabolic benefits for adults who are overweight or obese in a randomized, crossover, controlled feeding trial

Abstract

Background: A Mediterranean-style eating pattern (Mediterranean Pattern) is often described as being low in red meat. Research shows that lean, unprocessed red meat can be incorporated into healthy eating patterns to improve cardiometabolic disease (CMD) risk factors.

Objective: We assessed the effects of consuming different amounts of lean, unprocessed red meat in a Mediterranean Pattern on CMD risk factors. We hypothesized that consuming a Mediterranean Pattern would improve CMD risk factors and that red meat intake would not influence these improvements.

Design: In an investigator-blinded, randomized, crossover, controlled feeding trial, 41 subjects [mean ± SD age: 46 ± 2 y; mean ± SD body mass index (kg/m2): 30.5 ± 0.6] were provided with a Mediterranean Pattern for two 5-wk interventions separated by 4 wk of self-selected eating. The Mediterranean Patterns contained ∼500 g [typical US intake (Med-Red)] and ∼200 g [commonly recommended intake in heart-healthy eating patterns (Med-Control)] of lean, unprocessed beef or pork per week. Red meat intake was compensated by poultry and other protein-rich foods. Baseline and postintervention outcomes included fasting blood pressure, serum lipids, lipoproteins, glucose, insulin, and ambulatory blood pressure. The presented results were adjusted for age, sex, and body mass at each time point (P < 0.05).

Results: Total cholesterol decreased, but greater reductions occurred with Med-Red than with Med-Control (-0.4 ± 0.1 and -0.2 ±0.1 mmol/L, respectively, intervention × time = 0.045]. Low-density lipoprotein decreased with Med-Red but was unchanged with Med-Control [-0.3 ± 0.1 and -0.1 ± 0.1 mmol/L, respectively, intervention × time = 0.038], whereas high-density lipoprotein (HDL) concentrations decreased nondifferentially [-0.1 ± 0.0 mmol/L]. Triglycerides, total cholesterol:HDL, glucose, and insulin did not change with either Med-Red or Med-Control. All blood pressure parameters improved, except during sleep, independent of the red meat intake amount.

Conclusions: Adults who are overweight or moderately obese may improve multiple cardiometabolic disease risk factors by adopting a Mediterranean-style eating pattern with or without reductions in red meat intake when red meats are lean and unprocessed. This trial was registered at clinicaltrials.gov as NCT02573129.

FIGURE 1

Changes in lipids and lipoproteins after consuming a Med-Red or Med-Control diet for 5 wk. Results are presented as LS means ± SEMs (n = 41). Data were analyzed using a doubly repeated-measures ANOVA adjusted for age, sex, and body mass at each time point. *Nondifferential change over time. ^†Differential response between Med-Red and Med-Control when intervention × time P value < 0.05. ^‡Intervention-specific change over time indicated by intervention × time P < 0.05. ApoB results followed a similar pattern as LDL cholesterol and are available in Supplemental Tables 1 and 2. Conversion factors are available at: http://www.amamanualofstyle.com/page/si-conversion-calculator. ApoB, apolipoprotein B; LS, least squares; Med-Control, Mediterranean-style eating pattern with ∼200 g lean, unprocessed red meat/wk; Med-Red, Mediterranean-style eating pattern with ∼500 g lean, unprocessed red meat/wk.

FIGURE 2

Changes in systolic blood pressures from consuming a Med-Red or Med-Control diet for 5 wk. Results are presented as LS means ± SEMs (n = 41). Data were analyzed using a doubly repeated-measures ANOVA adjusted for age, sex, and body mass at each time point. *Change over time. ¹Waking blood pressure: 0800–2100. ²Sleeping blood pressure: 2230–0730. Diastolic blood pressure results followed similar patterns and are available in Supplemental Tables 1 and 2. LS, least squares; Med-Control, Mediterranean-style eating pattern with ∼200 g lean, unprocessed red meat/wk; Med-Red, Mediterranean-style eating pattern with ∼500 g lean, unprocessed red meat/wk.