Dietary patterns in association to cancer incidence and survival: concept, current evidence, and suggestions for future research.

Assessing diet through dietary patterns has become popular in diet-disease investigations due to the appealing simplicity of expressing several dietary exposures through one variable. Current evidence suggests that there may exist a priori and a posteriori dietary patterns that are consistently associated with reduced all-cause, as well as site-specific cancer risk across different populations. Typical examples include the Mediterranean dietary pattern, the Healthy Eating Index, a number of "healthy" a posteriori dietary patterns, and others. Despite their apparent differences, by inspecting their components it seems that multiple dietary patterns reflect core constituents of a healthy diet. Ongoing research is targeted to: (a) identify the common features underlying the beneficial-for-cancer-prevention dietary patterns, (b) decompose the estimated associations of dietary patterns with cancer risk to the individual associations of their components, and (c) construct dietary patterns for site-specific cancer risk prediction. Results of these and other initiatives could be helpful for public health policy makers and responsible bodies to (a) better formulate relevant messages for informing people about the components of cancer-preventing diets, and (b) promote small changes in eating patterns that can lower cancer risk and improve cancer outcomes.