Adherence to the Mediterranean Diet is Associated With Lower Likelihood of Breast Cancer: A Case-Control Study

Abstract

Mediterranean diet has long been associated with human health. However, its relationship with breast cancer remains not well understood and appreciated. The aim of this work was to evaluate the association between adherence to the Mediterranean diet and its inherent constituents, with breast-cancer. Two-hundred-and-fifty consecutive, newly diagnosed breast-cancer female patients (56 ± 12 yr) and 250, 1-to-1 age-matched with the patients, controls, were studied. A standardized, validated questionnaire assessing various sociodemographic, clinical, lifestyle, and dietary characteristics, was applied through face-to-face interviews. Adherence to the Mediterranean diet was evaluated using the 11-components MedDietScore (theoretical range 0–55). Multiple logistic regression was applied to test the research hypothesis, whereas discriminant analysis was used to explore the strength of each component in relation to the outcome. One unit increase in the MedDietScore (i.e., greater adherence to the Mediterranean diet) was associated with 9% lower likelihood of having breast cancer (odds ratio = 0.91; 95% confidence interval, 0.86, 0.97). Decomposition of the MedDietScore revealed that the most important components and with beneficial effect were nonrefined cereals, vegetables, fruits, and alcohol, followed by red meat, but with unfavorable effect. A dietary recommendation for healthy eating, close to the Mediterranean dietary pattern, seems promising for breast cancer prevention.