タグ: Cardiovascular Risk Factors

Meta-Analysis Comparing Mediterranean to Low-Fat Diets for Modification of Cardiovascular Risk Factors

Meta-Analysis Comparing Mediterranean to Low-Fat Diets for Modification of Cardiovascular Risk Factors

Abstract

Background

Evidence from individual trials comparing Mediterranean to low-fat diets to modify cardiovascular risk factors remains preliminary.

Methods

We systematically searched MEDLINE, EMBASE, Biosis, Web of Science, and the Cochrane Central Register of Controlled Trials from their inception until January 2011, as well as contacted experts in the field, to identify randomized controlled trials comparing Mediterranean to low-fat diets in overweight/obese individuals, with a minimum follow-up of 6 months, reporting intention-to-treat data on cardiovascular risk factors. Two authors independently assessed trial eligibility and quality.

Results

We identified 6 trials, including 2650 individuals (50% women) fulfilling our inclusion criteria. Mean age of enrolled patients ranged from 35 to 68 years, mean body mass index from 29 to 35 kg/m2. After 2 years of follow-up, individuals assigned to a Mediterranean diet had more favorable changes in weighted mean differences of body weight (−2.2 kg; 95% confidence interval [CI], −3.9 to −0.6), body mass index (−0.6 kg/m2; 95% CI, −1 to −0.1), systolic blood pressure (−1.7 mm Hg; 95% CI, −3.3 to −0.05), diastolic blood pressure (−1.5 mm Hg; 95% CI, −2.1 to −0.8), fasting plasma glucose (−3.8 mg/dL, 95% CI, −7 to −0.6), total cholesterol (−7.4 mg/dL; 95% CI, −10.3 to −4.4), and high-sensitivity C-reactive protein (−1.0 mg/L; 95% CI, −1.5 to −0.5). The observed heterogeneity across individual trials could, by and large, be eliminated by restricting analyses to trials with balanced co-interventions or trials with restriction of daily calorie intake in both diet groups.

Conclusion

Mediterranean diets appear to be more effective than low-fat diets in inducing clinically relevant long-term changes in cardiovascular risk factors and inflammatory markers.

Effects of a Mediterranean-Style Diet on Cardiovascular Risk Factors

I have read an article which describes about effect of Mediterranean diet on cardiovascular risk factors. In Mediterranean countries, epidemiological evidence has been shown to low rate of cardiovascular death. It is derived from original diet pattern that people eat olive oil, nuts, vegetables, beans, fishes and red wine and don’t eat red meat, daily products and sweets so much. In this article, authors said that Mediterranean diets supplemented with olive oil or nuts have beneficial effects on such cardiovascular risks as plasma glucose, blood pressure, body weight, lipid profile and inflammatory marker factors compared with a low-fat diet. Although the authors had shown the epidemiological evidence, the discussion lacks the reason why only olive oil has beneficial effect on CRP but nuts doesn’t have.

Effects of a Mediterranean-Style Diet on Cardiovascular Risk Factors

Ramon Estruch, MD, PhD; Miguel A´ngel Marti´nez-Gonza´lez, MD, PhD; Dolores Corella, PhD; Jordi Salas-Salvado´, MD, PhD; Valentina Ruiz-Gutie´rrez, PhD; Mari´a Isabel Covas, PhD; Miguel Fiol, MD, PhD; Enrique Go´mez-Gracia, MD, PhD; Mari Carmen Lo´pez-Sabater, PhD; Ernest Vinyoles, MD, PhD; Fernando Aro´s, MD, PhD; Manuel Conde, MD, PhD; Carlos Lahoz, MD, PhD; Jose´ Lapetra, MD, PhD; Guillermo Sa´ez, MD, PhD; and 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 (Prevencio´n con Dieta Mediterra´nea [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.

Ann Intern Med. 2006; 145: 1-11.