Healthy diets promote health, growth and development, support active lifestyles, prevent nutrient deficiencies and excesses, communicable and noncommunicable diseases, foodborne diseases and promote wellbeing. The exact make-up of a diet will vary depending on individual characteristics, preferences and beliefs, cultural context, locally available foods and dietary customs. However, the basic principles of what constitutes healthy diets remain the same. In this document the Food and Agriculture Organization of the United Nations (FAO) and the World Health Organization (WHO) have formulated principles of what constitute healthy diets, underpinned by guidelines and other normative elements developed by the two Organizations. The principles provide the basis for the design of policies aimed at improving diet and for the assessment of the healthiness of diets.