Eggs are a highly nutritious and versatile food, providing high-quality protein, essential amino acids and a range of bioactive compounds with potential health benefits. This chapter explores the composition and nutritional profile of eggs, focusing on their proteins, amino acids, lipids, vitamins, and bioactive constituents such as choline, lutein, phospholipids, and peptides. The health effects of these components are examined in relation to cardiometabolic diseases, muscle protein synthesis, cognitive function, and inflammation. Particular attention is given to egg-derived peptides and their emerging roles in regulating blood pressure and modulating the immune system. The chapter also assesses the controversies surrounding dietary cholesterol and egg intake, discussing current evidence in the context of public health nutrition. In addition, the role of eggs in sustainable nutrition strategies and their potential in addressing malnutrition and ageing-related diseases is highlighted. By integrating molecular, clinical, and public health data, this chapter offers a comprehensive view of eggs as functional foods with translational relevance.