Preschool children's sensitivity to teacher-served portion size is linked to age related differences in leftovers.

A strong predictor of children's food intake at a meal is the amount they are served, and with a high percentage children attending preschool, there is a need to consider the relationship between portion size and intake in this context. In a two-part repeated measures study we investigated whether the portions teachers serve to children i) differ from those children would serve themselves and ii) impact food intake at a local preschool in Singapore. Part 1 (n = 37, 20 boys, 3.0-6.8 years) compared the quantity of food served, consumed and leftover across three serving methods: 'regular' teacher-serving; child self-served portions; and a deliberately large portion served by the teacher (150% of each child's average previous gram intake). Part 2 (n = 44, 23 boys, 2.4-6.2 years old) consisted of three additional observations of school-based servings outside of the experimental manipulation and enhance external validity of the study findings. Results indicated that serving size and intake was similar when the children and teachers served their 'regular' portions, but children consumed most overall when the teacher served the larger 150% portion. This was dependent on the child's age, with the oldest children being most responsive to the large portions while the youngest children tended to serve and consume a similar weight of food, regardless of the serving method. Though the younger children were generally served less than the older children, they consistently had more leftovers across all of the study observations. These data suggest that younger preschool children moderated food intake by leaving food in their bowl, and emphasise the unique influence of caregivers over children's eating behaviours outside of the home environment.