There are only a few areas in human nutrition and metabolism where biomarkers are routinely used to predict health and functional outcome. For instance, of the four major nutritional deficiencies, only iron deficiency can be precisely diagnosed by employing biomarkers. They therefore play a limited role in research and decision making, and intervention strategies are still mostly targeted at the population level. What is needed at this stage are biomarkers that are predictive of later functional health and that stay stable from infancy to childhood and adult health. Moreover, individual variability must be considered, taking into account the complexity of foods, lifestyle, and metabolic processes that contribute to health or disease. These factors present significant challenges when it comes to personalizing dietary advice for healthy or diseased individuals. This book focuses on the values and limitations of traditional nutritional biomarkers and on opportunities for new biomarkers. Contributions are divided into three parts: Methodologies with regard to global epidemiology; applications/end users, and future horizons. The main goal is to review recent developments and predict how exciting new technologies could be used to drive advances in nutrition-related health care.