Until recently, nutrition research concentrated on nutrient deficiencies and impairment of health. The aim of the traditional nutrition approach was to provide nutrients for the betterment of nutritional status of populations. Contemporary nutrition science, however, focuses on improving health of individuals through diet with the aim of health promotion and disease prevention at the community level. Food intake and, through which, biologically active nutrient exposure are key environmental factors involved in the pathogenesis and progression of the common polygenic, diet-related diseases (cardiovascular diseases, diabetes, cancer). There is a dynamic, mutual interaction between nutrition and human genome. The unravelling of the human genome has led to extensive studies in the field of nutrient and gene interaction and recognition of the role of nutrients in gene expression. An individual’s phenotype is the result of a complex interaction between these two. The existence of individual differences in gene sequences, single nucleotide polymorphisms (SNPs), results in differential response to environmental factors such as diet. Nutrigenomics and nutrigenetics are the two emerging multidisciplinary fields, within the global concept of nutritional genomics, that focus on studying the interactions between nutritional factors, genetic factors and health outcomes. Nutrigenomics sheds light on how the whole body responds to real foods using an integrated approach termed “systems biology”. The tools of systems biology are high throughput techniques (chip technology) for measurement of gene expression and gene polymorphisms (genomics) and techniques for measuring global protein expression (proteomics) and metabolite profile (metabolomics). Nutrigenomics provides a molecular genetic understanding for how biologically active food components affect health by altering the expression and/or structure of an individual’s genetic makeup. Whereas nutrigenetics examines the effect of genetic variation on the interaction between diet and disease. Today, it has been well recognized by the professionals involved in nutrition that an individual’s response to dietary intervention will depend on his and her genetic background and that this information may be used to promote human health and disease prevention. The goal of nutrigenomics and nutrigenetics is, therefore, to achieve more efficient individual dietary intervention strategies aimed at improving human health, and achieving healthy ageing. Anahtar Kelimeler : nütrisyonel genomik, nütrigenomik, nütrigenetik, sistem biyolojisi, tek nükleotid polimorfizmleri, bireyselleştirilmiş beslenme, diyet ilişkili hastalıkları önleme, nutritional genomics, nutrigenomics, nutrigenetics, systems biology, single nucleotide polymorphisms, personalized nutrition, diet-related disease prevention