ABSTRACT
This chapter provides an overview of the importance of diets and food systems in shaping nutrition. Food systems are meant to provide food that is healthy, of sufficient quality and quantity, affordable, safe and culturally acceptable. The first consideration is quantity. For optimal nutrition, diets must be adequate in energy to maintain life, support physical activity and maintain a healthy body weight, but without excessive consumption of dietary energy. The second consideration is quality – the types of foods consumed and their diversity. A broad range of social, economic, demographic, and psychological factors influence the diets that people eat. Major transformations will be needed to reorient the food system towards the production, distribution, processing and sale of foods aligned with healthy diets. The impact would be to improve the health and well-being of billions of people. Malnutrition is to blame for a significant proportion of global ill-health.
