research on primary cancer prevention and to develop effectivestrategies such as those that might be related to nutrition. Manynutrients – fatty acids, carbohydrates, vitamins B, D, carotenoids,phytoestrogens, fiber – have been described to have a potentialimpact on tumor development in animal experiments and popula-tion studies, but there is little support revealed by epidemiologicalstudies [4]. Issues such as measurement error in nutritional assess-ment, lack of sufficient follow-up and the differences in timing ofexposure may contribute to the discrepancies among epidemio-logical studies. Another source of variation that is not taken intoaccount in epidemiological studies is genomic diversity in
tumorphenotypes. Indeed, different forms of breast cancer can be iden-tified through specific gene expression profiles which correspondto different disease outcomes and sensitivity to treatment and arelikely to be associated to different risk factors [5].This review focuses on the relationship between breast cancerand some specific nutrients, dietary patterns, as well as alcoholintake and obesity, based on recent epidemiological studies.