Mediterraan dieet beter dan vetarm dieet tegen hart- en vaatziektes.*

Uit een Spaans onderzoek onder 772 ouderen met of diabetes, hoge bloeddruk of hoog cholesterol blijkt dat een mediterraan dieet met olijfolie, volkoren granen en noten de risicofactoren op hart- en vaatziektes duidelijk doen verlagen dit in tegenstelling tot een vetarm dieet dat nauwelijks tot een verbetering leidt.

Behalve dat zowel de bloeddruk, cholesterol- en suikerwaarde duidelijk verbeterde was het voor deze mensen veel makkelijker om hun dieet vast te houden dit in tegenstelling tot de mensen met het vetarme dieet.
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*
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.

*For a list of additional PREDIMED Study Investigators, see the Appendix. ( Juli 2006)