Spontaneous classification of foods by elementary school-aged children.

This study examined children's conceptions about nutrients and the dimensions underlying their classifications of foods into groups. Children aged 5 to 11 (59 girls and 56 boys) placed 71 foods into groups by whatever criteria they wished. The bases of these classifications were recorded, as were the children's answers to questions about nutrients and their responses in tasks assessing cognitive developmental level. A cluster analysis of the classification data yielded four major groups. However, these groups differed in several respects from the Basic Four food groups generally taught in nutrition education, in ways including the presence of a sweets groups. Multidimensional scaling analysis revealed common underlying dimensions of sweet versus nonsweet foods and meal entrees versus drinks and breakfast foods, suggesting that perceptual, functional, and physical properties of foods influenced food classifications by children regardless of cognitive development level. However, only "concrete operational" children were substantially influenced by dimensions involving degree of processing of foods and origin of foods in plants or animals. Understanding of nutrients improved with cognitive developmental level, but generally poor understanding was evident. The results highlight the need to design health education curricula that are appropriate to students' cognitive developmental levels and to their naturally occurring conceptualizations.