There have been marked changes in eating habits perceptions of body image; these are currently very important with reports of nutritional deficiency and obesity, and are a large public health concern among children, adolescents, and adults. But what do children and adolescents know about the nutritiondigestion process and the basic concepts involved, and adequate eating behaviours for good health? How is this theme developed in state and private schools? These questions led to a study of the nature of practices developed by science and biology teachers and the knowledge shown by students in schools. Results revealed inadequate teaching methodology when dealing with the digestion process and the specific concepts involved in these themes, which leads to student disinterest and practically no change in their common understanding of the subject. Digestion and nutrition processes, as well as their health implications are seen as phenomena apart from student's life similar to how they are presented in the school text books. The dynamics of eating interrelations between living creatures are superficially covered in ecology and little attention is paid to the behavioural, morphological, and physiological changes involved. Considering these results we propose content based on an ecological approach directed towards specific experimental activities, games, and the co-evolutive interactions of living beings - social and biological aspects - to start students thinking about and criticising current social trends and our biological needs in relation to eating and health.
Science teaching; Digestion; Nutrition; Eating education; Systemic approach