Children appear to consider food as anything useful taken into an organism’s body, including water, minerals and, in the case of plants, carbon dioxide or even sunlight. When referring to starch in the context of plant nutrition, a child’s typical comment was ‘starch is not food because it is made not eaten’. 1 When Eisen and Stavy 2 asked advanced high school and university students ‘What does food mean to you?’, the responses included the following:

• essential materials 24 per cent; • energy source 40 per cent; • materials for building the body 14 per cent; • both energy and building materials 11 per cent.