Prediagnostic intake of dairy products and dietary calcium and colorectal cancer survival--results from the EPIC cohort study.
Dik VK., Murphy N., Siersema PD., Fedirko V., Jenab M., Kong SY., Hansen CP., Overvad K., Tjønneland A., Olsen A., Dossus L., Racine A., Bastide N., Li K., Kühn T., Boeing H., Aleksandrova K., Trichopoulou A., Trichopoulos D., Barbitsioti A., Palli D., Contiero P., Vineis P., Tumino R., Panico S., Peeters PHM., Weiderpass E., Skeie G., Hjartåker A., Amiano P., Sánchez M-J., Fonseca-Nunes A., Barricarte A., Chirlaque M-D., Redondo M-L., Jirström K., Manjer J., Nilsson LM., Wennberg M., Bradbury KE., Khaw K-T., Wareham N., Cross AJ., Riboli E., Bueno-de-Mesquita HB.
BACKGROUND: We investigated whether prediagnostic reported intake of dairy products and dietary calcium is associated with colorectal cancer survival. METHODS: Data from 3,859 subjects with colorectal cancer (42.1% male; mean age at diagnosis, 64.2 ± 8.1 years) in the European Investigation into Cancer and Nutrition cohort were analyzed. Intake of dairy products and dietary calcium was assessed at baseline (1992-2000) using validated, country-specific dietary questionnaires. Multivariable Cox regression models were used to calculate HR and corresponding 95% confidence intervals (CI) for colorectal cancer-specific death (n = 1,028) and all-cause death (n = 1,525) for different quartiles of intake. RESULTS: The consumption of total dairy products was not statistically significantly associated with risk of colorectal cancer-specific death (adjusted HR Q4 vs. Q1, 1.17; 95% CI, 0.97-1.43) nor that of all-cause death (Q4 vs. Q1, 1.16; 95% CI, 0.98-1.36). Multivariable-adjusted HRs for colorectal cancer-specific death (Q4 vs. Q1) were 1.21 (95% CI, 0.99-1.48) for milk, 1.09 (95% CI, 0.88-1.34) for yoghurt, and 0.93 (95% CI, 0.76-1.14) for cheese. The intake of dietary calcium was not associated with the risk of colorectal cancer-specific death (adjusted HR Q4 vs. Q1, 1.01; 95% CI, 0.81-1.26) nor that of all-cause death (Q4 vs. Q1, 1.01; 95% CI, 0.84-1.21). CONCLUSIONS: The prediagnostic reported intake of dairy products and dietary calcium is not associated with disease-specific or all-cause risk of death in patients diagnosed with colorectal cancer. IMPACT: The impact of diet on cancer survival is largely unknown. This study shows that despite its inverse association with colorectal cancer risk, the prediagnostic intake of dairy and dietary calcium does not affect colorectal cancer survival.