This is a comprehensive and authoritative guide that bridges the science of nutrition with its practical application in clinical and community settings. Nutrition plays a pivotal role in the prevention, management, and recovery from disease. The second edition of the book has been thoroughly revised and expanded to reflect the latest advances in nutrition science, diet therapy, and evidence-based practice. It provides an in-depth understanding of nutritional requirements across the life cycle, ranging from infancy, adolescence, pregnancy, and lactation to adulthood and geriatric nutrition, alongside detailed dietary management of a wide spectrum of clinical conditions. Covering 34 well-structured chapters, the text addresses medical nutrition therapy for gastrointestinal disorders, diabetes, cardiovascular diseases, renal and liver disorders, obesity, undernutrition, burns, cancer, metabolic disorders, and food allergies. Special emphasis has been placed on emerging and contemporary areas such as polycystic ovary syndrome (PCOS), emotional health and nutrition, personalized nutrition, and sports nutrition, making the book highly relevant to current healthcare needs. The content is based on the latest ICMR?NIN Recommended Dietary Allowances (2020, updated 2024), ensuring scientific accuracy and clinical relevance. Complex concepts are presented in a clear, systematic, and reader-friendly manner, supported by practical guidelines that can be readily applied in hospitals, clinics, and everyday practice. Designed for undergraduate and postgraduate students of nutrition and dietetics, this book is equally valuable for dietitians, clinicians, academicians, healthcare professionals, patients, caregivers, and health-conscious readers. With its balanced blend of theory, clinical insight, and practical application, Principles of Therapeutic Nutrition and Dietetics serves as an indispensable reference for those committed to improving health through informed dietary choices.