Mediterranean diet and colorectal cancer risk: results from a European cohort

The authors investigated the association of adherence to Mediterranean diet with colorectal cancer (CRC) risk in the European Prospective Investigation into Cancer and nutrition study. Adherence to Mediterranean diet was expressed through two 10-unit scales, the Modified Mediterranean diet score (MMDS) and the Centre-Specific MMDS (CSMMDS). Both scales share the same dietary components but differ in the cut-off values that were used for these components in the construction of the scales. Adjusted hazard ratios (HR) for the associations of these scales with CRC incidence were estimated. After 5,296,617 person-years of follow-up, 4,355 incident CRC cases were identified. A decreased risk of CRC, of 8 and 11 % was estimated when comparing the highest (scores 6-9) with the lowest (scores 0-3) adherence to CSMMDS and MMDS respectively. For MMDS the HR was 0.89 (95 % confidence interval (CI): 0.80, 0.99). A 2-unit increment in either Mediterranean scale was associated with a borderline statistically significant 3 to 4 % reduction in CRC risk (HR for MMDS: 0.96; 95 % CI: 0.92, 1.00). These associations were somewhat more evident, among women, were mainly manifested for colon cancer risk and their magnitude was not altered when alcohol was excluded from MMDS. These findings suggest that following a Mediterranean diet may have a modest beneficial effect on CRC risk.