Book excerpt: Nutrition in the Prevention and Treatment of Disease, Fourth Edition, is a compilation of current knowledge in clinical nutrition and an overview of the rationale and science base of its application to practice in the prevention and treatment of disease. In its fourth edition, this text continues the tradition of incorporating new discoveries and methods related to this important area of research Generating and analyzing data that summarize dietary intake and its association with disease are valuable tasks in treating disease and developing disease prevention strategies. Well-founded medical nutrition therapies can minimize disease development and related complications. Providing scientifically sound, creative, and effective nutrition interventions is both challenging and rewarding. - Two new chapters on metabolomics and translational research, which have come to be used in nutrition research in recent years. The new areas of study are discussed with the perspective that the application of the scientific method is by definition an evolutionary process. - A new chapter on Genetics and Diabetes which reviews the latest research on causal genetic variants and biological mechanisms responsible for the disease, and explores potential interactions with environmental factors such as diet and lifestyle. - Includes all major "omics" – the exposome, metabolomics, genomics, and the gut microbiome. - Expands the microbiota portions to reflect complexity of diet on gut microbial ecology, metabolism and health