Mediterranean Diet Reduces 24-Hour Ambulatory Blood Pressure, Blood Glucose, and Lipids

Background

The PREvención con DIeta MEDiterránea (PREDIMED) trial showed that Mediterranean diets (MedDiets) supplemented with either extra virgin olive oil or nuts reduced cardiovascular events, particularly stroke, compared with a control, lower fat diet. The mechanisms of cardiovascular protection remain unclear.

Objective

We evaluated the 1-year effects of supplemented MedDiets on 24-hour ambulatory blood pressure (BP), blood glucose, and lipids.

Design

Randomized, parallel-design, controlled trial was conducted in 2 PREDIMED sites. Diets were ad libitum, and no advice on increasing physical activity or reducing sodium intake was given.

Method

Participants were 235 subjects (56.5% women; mean age, 66.5 years) at high cardiovascular risk (85.4% with hypertension). Adjusted changes from baseline in mean systolic BP were −2.3 (95% confidence interval [CI], −4.0 to −0.5) mm Hg and −2.6 (95% CI, −4.3 to −0.9) mm Hg in the MedDiets with olive oil and the MedDiets with nuts, respectively, and 1.7 (95% CI, −0.1 to 3.5) mm Hg in the control group (P<0.001). 

Result

Respective changes in mean diastolic BP were −1.2 (95% CI, −2.2 to −0.2), −1.2 (95% CI, −2.2 to −0.2), and 0.7 (95% CI, −0.4 to 1.7) mm Hg (P=0.017). Daytime and nighttime BP followed similar patterns. Mean changes from baseline in fasting blood glucose were −6.1, −4.6, and 3.5 mg/dL (P=0.016) in the MedDiets with olive oil, MedDiets with nuts, and control diet, respectively; those of total cholesterol were −11.3, −13.6, and −4.4 mg/dL (P=0.043), respectively. 

Conclusion

In high-risk individuals, most with treated hypertension, MedDiets supplemented with extra virgin olive oil or nuts reduced 24-hour ambulatory BP, total cholesterol, and fasting glucose.