Objective: The role of diet on colorectal cancer has been considered in terms of single foods and nutrients, but less frequently in terms of dietary patterns.
Methods: Data were derived from an Italian case-control study, including 1,225 subjects with cancer of the colon, 728 subjects with rectal cancer, and 4,154 hospital controls. We identified dietary patterns on a selected set of nutrients through principal component factor analysis. Odds ratios (OR) and 95% confidence intervals for both cancers were estimated using unconditional multiple logistic regression.
Results: We identified 5 major dietary patterns. Direct associations were observed between the Starch-rich pattern and both cancer of the colon (OR = 1.68) and of the rectum (OR = 1.74). Inverse relationships were found between the Vitamins and fiber pattern and rectal cancer (OR = 0.61), between the Unsaturated fats (animal source) and the Unsaturated fats (vegetable source) and cancer of the colon (OR = 0.80 and OR = 0.79, respectively). No other significant association was found.
Conclusions: The Starch-rich pattern is potentially an unfavorable indicator of risk for both colon and rectal cancer, whereas the Vitamins and fiber pattern is associated with a reduced risk of rectal cancer and the Unsaturated fats patterns with a reduced risk of colon cancer.