Olive oil intake and breast cancer risk in the Mediterranean countries of the European prospective investigation into cancer and nutrition (EPIC) study
Menée auprès de 62 284 femmes ménopausées d'origine italienne, espagnole ou grecque, cette étude prospective, couplée à l'étude EPIC, évalue l'association entre la consommation d'huile d'olive dans les pays méditerranéens et le risque de cancer du sein (1 256 cas ; durée moyenne de suivi : 9 ans)
Although there is some evidence suggesting that olive oil could reduce breast cancer risk, the epidemiological data is still relatively limited, not entirely consistent and mainly based on case-controls studies. Therefore, we prospectively assessed the association between olive oil and breast cancer risk in postmenopausal women from the Mediterranean cohorts within the European Prospective Investigation into Cancer and Nutrition (EPIC). The analysis included 62,284 postmenopausal women recruited from Spain, Italy and Greece who had complete dietary data (collected from validated country-specific dietary questionnaires). Risk of breast cancer (overall and by hormone receptor subtypes) was assessed using HRs obtained from Cox proportional hazards regression, while adjusting for known breast cancer risk factors. After a mean follow-up of 9 years, 1,256 women were diagnosed with a primary incident invasive breast cancer. The multivariate HRs for BC risk by olive oil intake (highest vs. lowest tertile of g/day/2000kcal) were 1.07 (95% CI: 0.91, 1.25) in the adjusted model, 1.06 (95% CI: 0.91, 1.24) in the model additionally adjusted for reproductive-related factors, and 1.10 (95% CI: 0.92, 1.31) for the model additionally adjusted for dietary factors. There was no association between olive oil and risk of oestrogen or progesterone receptor-positive tumours, but a suggestion of a negative association with estrogens and progesterone receptor-negative tumours. The results from this prospective study showed that olive oil consumption during adult life was not associated with risk of breast cancer. However, larger prospective studies are still needed to explore possible differences related to hormone receptor status. (c) 2012 Wiley-Liss, Inc.