Diabetes risk reduction diet and colorectal cancer risk.

Background Diabetes has been associated with colorectal cancer (CRC). We aimed at evaluating whether adherence to a diabetes risk reduction diet (DRRD) could favorably influence the risk of CRC. Methods Data came from a multicentric Italian case-control study including 1,953 histologically confirmed CRC cases and 4,154 hospital controls admitted for acute non-neoplastic diseases. Diet was assessed through a validated and reproducible food frequency questionnaire. The DRRD score was computed assigning higher values for higher consumption of cereal fiber, fruit, coffee, nuts and a higher polyunsaturated/saturated fats ratio and for lower glycemic index and lower consumption of red/processed meat and sweetened beverage and fruit juice. The odds ratios (ORs) and the corresponding 95% confidence intervals (CIs) of CRC according to the DRRD score were obtained using logistic regression models adjusting for total energy intake and other major confounders. Results The DRRD was inversely related to CRC risk. The ORs of CRC were 0.77 (95% CI = 0.67-0.89) for the third versus first score tertile (p trend <0.001) and 0.92 (95% CI = 0.87-0.96) for a 3-point increment in the score. Inverse associations were observed for colon and rectal cancer and were consistent in strata of sex, age and other major covariates. Conclusion A higher adherence to a DRRD was inversely associated with CRC risk. Impact Given the high incidence and mortality rates of CRC, adherence to a DRRD can have relevant prevention and public health implications.