Associations between Dietary Patterns and Incident Colorectal Cancer in 114,443 Individuals from the UK Biobank: A Prospective Cohort Study.

Background: Diet-disease association studies increasingly use dietary patterns (DP) to account for the complexity of the exposure. We assessed if a DP associated with type 2 diabetes mellitus, cardiovascular disease, and all-cause mortality is also associated with colorectal cancer.

Methods: We used reduced rank regression on 24-hour recall data to identify DPs, explaining the maximum variation in four nutrient-response variables: energy density, saturated fatty acids, free sugars, and fiber density. Cox proportional hazards models examined prospective associations between DP adherence (coded in a continuous scale as z-scores as well as in quintiles) and incident colorectal cancer. Subgroup analyses were conducted for tumor site, age, and sex.

Results: After exclusions, 1,089 colorectal cancer cases occurred in 114,443 participants over a median follow-up of 8.0 years. DP1 was characterized by increased intake of chocolate and confectionery; butter; low-fiber bread; red and processed meats; and alcohol, as well as low intake of fruits, vegetables, and high-fiber cereals. After accounting for confounders, including body mass, there were positive linear associations between DP1 and incident overall colorectal cancer (HR of quintile 5 vs. 1, 1.34; 95% confidence interval, 1.16-1.53, Ptrend = 0.005) and rectal cancer (HR of quintile 5 vs. 1, 1.58; 95% confidence interval, 1.27-1.96, Ptrend = 0.009) but not for proximal or distal colon cancers. No DP2-colorectal cancer association was observed.

Conclusions: A DP previously associated with cardiometabolic disease is also associated with incident colorectal cancer, especially rectal cancers.

Impact: These consistent associations of particular food groups with both cardiometabolic disease and this diet-related cancer strengthen the evidence base for holistic population dietary guidelines to prevent ill-health.