Dietary patterns and the risk of colorectal cancers and adenomas

The association of colorectal cancer risk with select foods has been evaluated by dietary pattern analysis. This review of the literature was conducted to thoroughly examine the available evidence for the association between dietary patterns and colorectal cancers and adenomas. A total of 32 articles based on worldwide epidemiological studies were identified. Pattern identification was achieved by exploratory data analyses (principal component, factor, and cluster analyses) in most articles, and only a few used a priori-defined scores. Dietary patterns named as healthy, prudent, fruit and vegetables, fat-reduced/diet foods, vegetable/fish/poultry, fruit/whole grain/dairy, and healthy eating index-2005, recommended food and Mediterranean diet scores were all associated with reduced risk of colorectal cancer and the risk estimates varied from 0.45 to 0.90. In contrast, diets named Western, pork-processed meat-potatoes, meat-eaters, meat and potatoes, traditional patterns, and dietary risk and life summary scores were associated with increased risk of colorectal cancer with risk estimates varying from 1.18 to 11.7. Dietary patterns for adenomas were consistent with those identified for colorectal cancer.