Book excerpt: Nutrients can act as signalling molecules to initiate or mediate signalling transduction that regulates cell function and homeostasis. As such, altered nutrient status has been linked to dysregulated transcripts and protein expression, which affects mitochondrial function, autophagy, inflammation, metabolism and even gut microbiota. This book disseminates the cutting-edge knowledge pertaining to nutritional signalling activities in metabolism and metabolic derangements (e.g., obesity and diabetes), which covers the regulatory mechanisms and dietary interventions for disease prevention. This book represents current nutritional and metabolic research. From the basic (molecular science) perspective, it covers metabolomics, proteomics, nutrigenomics, nuclear receptors and transcription factors, inflammatory pathways, autophagy, mitochondrial health and gut microbiota. From the clinical (translational science) perspective, this book covers clinical trials, precision nutrition, maternal nutrition and transgenerational health, and allometric scaling of dietary bioactives in translational metabolic research. It brings to the reader in-depth understanding of the nutritional aspect, cellular and molecular biology, as well as pathophysiology of obesity and diabetes. In addition, each chapter in this book includes a component of future direction or intervention perspective, making the new knowledge transformative and translational. Aimed at researchers and professionals interested in nutrition, dietetics and metabolic disorders, this book will also appeal to health science researchers.