Effects of a Mediterranean-Style Diet on Cardiovascular Risk Factors

Ann Intern Med 4 July 2006, Volume 145 Issue 1, 1-11. © 2006 American
Medical Association. All rights reserved.
Effects of a Mediterranean-Style Diet on Cardiovascular Risk Factors - A
Randomized Trial, Ramon Estruch, MD, PhD; Miguel Ángel Martínez-González,
MD, PhD; Dolores Corella, PhD; Jordi Salas-Salvadó, MD, PhD; Valentina
Ruiz-Gutiérrez, PhD; María Isabel Covas, PhD; Miguel Fiol, MD, PhD; Enrique
Gómez-Gracia, MD, PhD; Mari Carmen López-Sabater, PhD; Ernest Vinyoles, MD,
PhD; Fernando Arós, MD, PhD; Manuel Conde, MD, PhD; Carlos Lahoz, MD, PhD;
José Lapetra, MD, PhD; Guillermo Sáez, MD, PhD; Emilio Ros, MD, PhD, for the
PREDIMED Study Investigators. Correspondence to Ramon Estruch, MD, PhD

Background: The Mediterranean diet has been shown to have beneficial effects
on cardiovascular risk factors.

Objective: To compare the short-term effects of 2 Mediterranean diets versus
those of a low-fat diet on intermediate markers of cardiovascular risk.

Design: Substudy of a multicenter, randomized, primary prevention trial of
cardiovascular disease (Prevención con Dieta Mediterránea [PREDIMED] Study).

Setting: Primary care centers affiliated with 10 teaching hospitals.

Participants: 772 asymptomatic persons 55 to 80 years of age at high
cardiovascular risk who were recruited from October 2003 to March 2004.

Interventions: Participants were assigned to a low-fat diet (n = 257) or to
1 of 2 Mediterranean diets. Those allocated to Mediterranean diets received
nutritional education and either free virgin olive oil, 1 liter per week (n
= 257), or free nuts, 30 g/d (n = 258). The authors evaluated outcome
changes at 3 months.

Measurements: Body weight, blood pressure, lipid profile, glucose levels,
and inflammatory molecules.

Results: The completion rate was 99.6%. Compared with the low-fat diet, the
2 Mediterranean diets produced beneficial changes in most outcomes. Compared
with the low-fat diet, the mean changes in the Mediterranean diet with olive
oil group and the Mediterranean diet with nuts group were -0.39 mmol/L (95%
CI, -0.70 to - 0.07 mmol/L) and - 0.30 mmol/L (CI, -0.58 to - 0.01 mmol/L),
respectively, for plasma glucose levels; -5.9 mm Hg (CI, -8.7 to -3.1 mm Hg)
and - 7.1 mm Hg (CI, -10.0 to -4.1 mm Hg), respectively, for systolic blood
pressure; and -0.38 (CI, -0.55 to - 0.22) and - 0.26 (CI, -0.42 to -0.10),
respectively, for the cholesterol-high-density lipoprotein cholesterol
ratio. The Mediterranean diet with olive oil reduced C-reactive protein
levels by 0.54 mg/L (CI, 1.04 to 0.03 mg/L) compared with the low-fat diet.

Limitations: This short-term study did not focus on clinical outcomes.
Nutritional education about low-fat diet was less intense than education
about Mediterranean diets.

Conclusion: Compared with a low-fat diet, Mediterranean diets supplemented
with olive oil or nuts have beneficial effects on cardiovascular risk
factors.

Pengaruh diet Mediterrania terhadap Faktor Risiko Kardiovaskuler

Telah diketahui bahwa diet Mediterrania dapat memperbaiki faktor risiko
penyakit kardiovaskuler (PKV). Para ahli di Spanyol hendak membandingkan
pengaruh diet Mediterrania (tinggi lemak golongan MUFA) dibanding diet
rendah lemak terhadap faktor risiko PKV.

Penelitian berlangsung dari 2003 sampai 2004, diambil dari 10 sentra
kesehatan dan dilakukan randomisasi, melibatkan 772 pasien asimptomatik
risiko tinggi PKV, berusia 55-80 tahun. Pasien di-randomized menjadi
kelompok diet rendah lemak (n=257) atau salah satu dari dua jenis diet
Mediterrania, yaitu kelompok yang mendapat 1 liter perminggu virgin olive
oil (n=257) atau 30g perhari kacang (n=258). Evaluasi dilakukan tiap 3 bulan
terhadap berat badan, tekanan darah, profil lipid, kadar gula darah, dan
penanda inflamasi.

Ternyata dibanding diet rendah lemak, kedua diet Mediterrania yang tinggi
lemak MUFA lebih unggul dalam hal menurunkan kadar gula darah, menurunkan
tekanan sistolik, menurunkan rasio kolesterol terhadap HDL. Diet
Mediterrania dengan olive oil menurunkan kadar C-reactive protein (CRP
adalah penanda inflamasi) dibanding diet rendah lemak.

Kesimpulan dari penelitian ini adalah diet Mediterrania yang tinggi lemak
MUFA (sumber MUFA dari olive oil atau kacang) lebih unggul dalam memperbaiki
faktor risiko PKV dibanding diet rendah lemak.