Nutritional genomics (nutrigenomics) is the application of high-throughput functional genomics technologies to nutritional science lying in the interface between the nutritional environment and genetic process. It seeks to provide a molecular genetic understanding of how common dietary nutrition affects health by altering the expression or structure of an individual's genetic makeup. On the other hand, nutrigenetics is significantly different from nutrigenomics since nutrigenetics has been used for decades in certain rare monogenic diseases such as phenylketonuria, and has the potential to provide a basis for personalized dietary recommendation based on the individual's specific genetic background in order to prevent common multifactorial disorders decades before their clinical manifestation. The human genome maps and SNP databases, together with the rapid development of tools suitable for investigating genetic and epigenetic changes in small tissue biopsies provide the means to begin the test hypothesis about the mechanisms by which diet influences disease risk including cancer directly in human subjects, could be inevitable flatforms for clinical application to achieve targeted therapy in near future.