A Mediterranean-style diet with lean beef lowers blood pressure and improves vascular function: a randomized controlled trial

Authors: FLEMING, JENNIFER - Pennsylvania State University; KRIS-ETHERTON, PENNY - Pennsylvania State University; PETERSON, KRISTINA - Pennsylvania State University; Baer, David

Submitted to: Current Developments in Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/18/2025
Publication Date: N/A
Citation: N/A

Interpretive Summary: Cardiovascular disease (CVD) is the leading contributor to global disease burden representing 30% of total deaths and disability in individuals aged 60 years and older. During aging, structural and functional changes occur in the vessel wall that decrease arterial function and increase the susceptibility of developing CVD. Structural changes that occur in the large elastic arteries during aging promote arterial stiffness owing to the gradual loss of arterial elasticity. Results from numerous studies demonstrate that increased arterial stiffness predicts cardiovascular events and/or mortality and may explain some of the residual cardiovascular risk observed in individuals with well-controlled hypertension. The effect of a Mediterranean pattern diet on these measures of vascular health has not been investigated. The objective of the present study was to evaluate the effects of a traditional Mediterranean diet (0.5 oz/day/lean beef/2100 kcal) as well as two Med diets containing 2.5 oz. and 5.5 oz/day/lean beef/2100 kcal compared with an average American control diet on brachial and central systolic, as well as diastolic blood pressure, and arterial stiffness. A multicenter, 4-period randomized, crossover, controlled-feeding study was conducted. The consumption of a Med style dietary pattern containing 0.5 to 5.5 oz/day of lean beef significantly reduced brachial systolic and diastolic blood pressure when compared to an average American diet containing 2.5 oz/day of beef. Greater improvements in central systolic and diastolic blood pressures and arterial stiffness were observed following consumption of Med diet with lean beef in amounts up to 2.5 oz/day when compared to an average American diet. These findings suggest that incorporation of lean beef into a healthy dietary pattern such as the Med diet does not adversely affect CVD risk and improves vascular health. Thus, a Med diet with 0.5-2.5 oz/day of lean beef is option for a healthy dietary pattern and may benefit those who wish to consume lean red meat.

Technical Abstract: Extensive evidence demonstrates that a Mediterranean (Med) dietary pattern improves cardiovascular risk factors. Increased central systolic pressure and arterial stiffness are novel independent predictors of CVD. The effect of a Med diet on these measures of vascular health has not been investigated. The objective of this study was to evaluate the effects of a Med diet with 0.5 oz/day (MED0.5), 2.5 oz/day (MED2.5) and 5.5 oz/day (MED5.5) of lean beef compared to an Average American diet (AAD) on measures of vascular function (brachial and central blood pressure, pulse wave velocity and augmentation index). A multicenter, 4-period randomized, crossover, controlled-feeding study was conducted at Penn State University and USDA-Beltsville. Participants were generally healthy normal to overweight/obese males and females (n=66). PWV, central systolic and diastolic blood pressure were measured using the SphygmoCor XCEL-System. Endpoints were assessed at baseline and the end of each 4-week diet period. There was a significant diet effect for PWV (p<0.01); PWV was lower following MED0.5 (6.86 m/sec ± 0.14; p<0.05) and MED2.5 (6.84 m/sec ± 0.15; p<0.01) compared to the AAD (7.10 m/sec ± 0.14). Compared to the AAD, both the MED0.5 (-3.30 mmHg ± 0.76) and MED2.5 (-2.94 mmHg ± 0.76) elicited greater reductions in central systolic blood pressure. A similar pattern was observed for central diastolic pressure. Compared to AAD, all three MED diets significantly decreased brachial systolic and diastolic pressures (p<0.01 for all). Med diets containing 0.5 and 2.5 oz./day of lean beef improved brachial and central systolic and diastolic blood pressure and arterial stiffness. Our findings suggest that less than 2.5 oz/day of lean beef can be included in a Med diet with no adverse effect on vascular function.