This textbook explains the basic principles of biochemistry, nutrition, and dietetics and their application to health and disease. It presents a strong foundational understanding of these subjects; especially for nursing professionals who are at the forefront of patient care. This edition not only covers the essential scientific principles but also incorporates recent advances and the shifting health priorities of India. In response to evolving healthcare needs and feedback from educators, several key changes and enhancements have been introduced. The book has also been updated to align with the latest syllabus mandated by the Indian Nursing Council (INC).