A study released Tuesday in the online edition of the British Medical Journal took aim at this very question. Researchers from the Harvard School of Public Health in Boston and the University of Athens Medical School in Greece looked at more than 23,000 Greek men and women participating in the European Prospective Investigation into Cancer and Nutrition (EPIC). Over the course of about eight and a half years, the researchers led by Harvard's Dimitrios Trichopoulos and the University of Athens' Antonia Trichopoulou compared the health of the participants against their adherence to a Mediterranean diet.
As the authors note, that the analysis indicates that the dominant components of the Mediterranean diet score as a predictor of lower mortality are moderate consumption of [alcohol], low consumption of meat and meat products, and high consumption of vegetables, fruits and nuts, olive oil, and legumes.
In some ways, looking for the 'active ingredients' in the health benefits of the Mediterranean diet may be a distraction, since it is the overall dietary pattern that matters most to health, said Dr. David Katz, director of the Prevention Research Center at Yale University School of Medicine in New Haven, Conn. Once you have a mostly plant based diet and eat few processed foods, almost any variation on the theme will be fine.
Despite its name, this diet is not typical of all Mediterranean cuisine. In Northern Italy, for instance, lard and butter are commonly used in cooking, and olive oil is reserved for dressing salads and cooked vegetables.[3] In North Africa, wine is traditionally avoided by Muslims. In both North Africa and the Levant, along with olive oil, sheep's tail fat and rendered butter (samna) are traditional staple fats.[4]