Nutritional Epidemiology is an area of epidemiology that involves research to examine the distribution of nutritional status and nutrition-related disease and analyze the role of nutrition in the etiology of disease among populations.

Nutritional epidemiologists identify natural history and causes of diet-related outcomes by quantifying health-related states or events and develop the methods to assess determinants for diet-related health problems. Nutritional epidemiologists are involved in the design of studies, collection and statistical analysis of data and interpretation and dissemination of epidemiologic evidences. Nutritional epidemiologic research helps inform evidence-based medicine and policy decisions, therefore targets for effective control and prevention of human disease in the population.