Sustainable and healthy nutrition is a hot topic. It is part of the curriculum in many types of schools and training programs, from vocational schools to the field of Oecotrophology. This knowledge repository contains all the facts related to classical nutrition science, viewed through the lens of sustainability and health. It provides well-founded answers, background information, and facts to impulse questions such as "What is sustainable nutrition?" "What lies behind a healthy diet?" "What does a balanced, needs-based diet mean?" and "Does it look the same for infants as it does for older adults?" Additionally, some global issues of our time, such as obesity and climate change, which have a direct or indirect connection to nutrition, are highlighted. This work is of interest to all teachers and trainers.