Daily Red Meat Intake does not Affect Improvements in Cardiovascular Disease Risk Factors Induced by Consuming the USDA's Healthy Mediterranean‐Style Eating Pattern
Authors: O'Connor Lauren E , Wright Amy J , Paddon‐Jones Douglas , Campbell Wayne W 
Published: November 2023

Background

The USDA's Healthy Mediterranean‐Style Eating Pattern (Med diet) is designed to reflect the eating pattern consumed in the Mediterranean region of the world which is associated with decreased risk of cardiovascular disease (CVD). Among the Med diet guidelines, it is suggested to limit red meat consumption.

Objective

The purpose of this study was to assess the effects of including higher amounts of minimally processed lean red meat (~one 2.5 oz. or 70g serving of beef or pork/day) in a Med diet on CVD risk factors, specifically blood lipids, lipoproteins, and blood pressures (BPs). Based on results from previous randomized controlled feeding studies using other healthy eating patterns, we hypothesized that consuming either rich or restricted amounts of red meat would not influence Med diet‐induced improvements in CVD risk factors.

Methods

In a randomized investigator‐blinded crossover study, 25 women and 13 men (aged 46 ± 2 y, BMI 30.6 ± 0.6 kg/m2) who were not already following a healthy eating pattern consumed a weight‐maintenance Med diet for two 5‐wk periods separated by a 4‐wk washout period. The Med diets were either restricted or rich in minimally processed lean red meat (5.5 oz./154g or 18.2 oz./510g of beef/pork per week, respectively). Both diets contained 20/40/40% of total energy from protein/carbohydrate/fat, respectively, with a fatty acid ratio of 22/11/7% of total energy from monounsaturated/polyunsaturated/saturated fats, respectively. At baseline and during the last week of each intervention fasting BPs, blood lipids and lipoproteins, and body composition (via a BOD POD®) were measured and subjects wore an ambulatory BP monitor for 24 hours. All data were analyzed by a doubly repeated measures ANOVA adjusted for age, body mass, and sex using Tukey‐Kramer adjusted p values with a significance level of p<0.05. Data are presented as adjusted least squares means and SEM.

Results

Consumption of a Med diet decreased all BP parameters over time (~3‐6 and ~2–5 mm Hg decrease in all systolic and diastolic BPs, respectively) and inclusion of higher amounts of minimally processed lean red meat did not influence results except for a greater reduction in waking diastolic BP with consumption of the Med diet rich in red meat (p=0.043). Similarly, consumption of a Med diet decreased all lipoprotein concentrations over time (total cholesterol: − 16 ± 4 and −9 ± 4, LDL: −10 ± 4 and −4 ± 4, and HDL: −4 ± 2 and −5 ± 2 for Med diet rich and restricted in red meat, respectively) and inclusion of higher amounts of red meat did not influence these results. Triglycerides, total cholesterol:HDL, body mass, and body composition did not change over time with either diet. Baseline CVD risk factor values did not differ between trials supporting an effective washout period.

Conclusion

Consumption of the USDA's Healthy Mediterranean‐Style Eating Pattern positively influenced cardiovascular disease risk factors which was not influenced by the inclusion of higher amounts of red meat.

Support or Funding Information

Beef Checkoff, Pork Checkoff, NIH UL1TR001108, and NIH 5T32DK076540‐08