Anatomy of health effects of Mediterranean diet: Greek EPIC prospective cohort studyBMJ 2009; 338 doi: http://dx.doi.org/10.1136/bmj.b2337 (Published 24 June 2009) Cite this as: BMJ 2009;338:b2337
- 1Department of Hygiene, Epidemiology and Medical Statistics, University of Athens, Medical School, 115 27 Athens, Greece
- 2Department of Epidemiology, Harvard School of Public Health, 677 Huntington Avenue, Boston, MA 02115, USA
- Correspondence to: D Trichopoulos
- Accepted 6 February 2009
Objective To investigate the relative importance of the individual components of the Mediterranean diet in generating the inverse association of increased adherence to this diet and overall mortality.
Design Prospective cohort study.
Setting Greek segment of the European Prospective Investigation into Cancer and nutrition (EPIC).
Participants 23 349 men and women, not previously diagnosed with cancer, coronary heart disease, or diabetes, with documented survival status until June 2008 and complete information on nutritional variables and important covariates at enrolment.
Main outcome measure All cause mortality.
Results After a mean follow-up of 8.5 years, 652 deaths from any cause had occurred among 12 694 participants with Mediterranean diet scores 0-4 and 423 among 10 655 participants with scores of 5 or more. Controlling for potential confounders, higher adherence to a Mediterranean diet was associated with a statistically significant reduction in total mortality (adjusted mortality ratio per two unit increase in score 0.864, 95% confidence interval 0.802 to 0.932). The contributions of the individual components of the Mediterranean diet to this association were moderate ethanol consumption 23.5%, low consumption of meat and meat products 16.6%, high vegetable consumption 16.2%, high fruit and nut consumption 11.2%, high monounsaturated to saturated lipid ratio 10.6%, and high legume consumption 9.7%. The contributions of high cereal consumption and low dairy consumption were minimal, whereas high fish and seafood consumption was associated with a non-significant increase in mortality ratio.
Conclusion The dominant components of the Mediterranean diet score as a predictor of lower mortality are moderate consumption of ethanol, low consumption of meat and meat products, and high consumption of vegetables, fruits and nuts, olive oil, and legumes. Minimal contributions were found for cereals and dairy products, possibly because they are heterogeneous categories of foods with differential health effects, and for fish and seafood, the intake of which is low in this population.
Contributors: AT is the principal investigator of the Greek EPIC study. She was responsible for the conception and design of the study, data collection, interpretation of results, and drafting the manuscript. CB was responsible for the statistical analysis and interpretation of results and drafting the manuscript. DT was the senior epidemiologist and contributed to study design and analysis and the drafting of the manuscript. All authors have seen and approved the final version of the manuscript. AT is the guarantor.
Funding: This study was supported by the Europe against Cancer Program of the European Commission, the Greek Ministries of Health and Education, and a grant to the Hellenic Health Foundation by the Stavros Niarchos Foundation. The study sponsors did not have any role in the study design; the collection, analysis, and interpretation of data; the writing of the report; or the decision to submit the paper for publication. Researchers were independent from funders.
Competing interests: None declared.
Ethical approval: All volunteers signed informed consent forms, and the study protocol was approved by ethics committees at the International Agency for Research on Cancer (Lyon, France) and the University of Athens, Medical School.
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