Nutrition for Healthy Ageing is a university-level textbook examining how nutrition supports health, function and quality of life across later adulthood. It explains how to interpret nutritional evidence and applies that reasoning to protein, calcium, vitamin D, dietary patterns, bone health, cardiometabolic health, sarcopenia, frailty and malnutrition. Mediterranean-style and plant-based diets are assessed with attention to study design, population, outcome definitions, uncertainty and practical adequacy. Sixteen chapters combine learning objectives, evidence tables, cases, critical-thinking tasks, assessments, a glossary and references. The accompanying Lecturer Companion includes teaching guidance, assessment support and reproducible student activities. Written for university learners and educators, the book distinguishes population guidance from individual clinical assessment and avoids unsupported disease-treatment, detox and rapid-weight-loss claims.