How big is a food portion? A pilot study in Australian families

It is not known whether individuals can accurately estimate the portion size of foods usually consumed relative to standard serving sizes in national food selection guides. The aim of the present cross-sectional pilot study was to quantify what adults and children deem a typical portion for a variety of foods and compare these with the serving sizes specified in the Australian Guide to Healthy Eating (AGHE).

Adults and children were independently asked to serve out their typical portion of 10 common foods (rice, pasta, breakfast cereal, chocolate, confectionary, ice cream, meat, vegetables, soft drink and milk). They were also asked to serve what they perceived a small, medium and large portion of each food to be. Each portion was weighed and recorded by an assessor and compared with the standard AGHE serving sizes.

Twenty-one individuals (nine mothers, one father, 11 children) participated in the study. There was a large degree of variability in portion sizes measured out by both parents and children, with means exceeding the standard AGHE serving size for all items, except for soft drink and milk, where mean portion sizes were less than the AGHE serving size. The greatest mean overestimations were for pasta (155%; mean 116 g; range 94-139 g) and chocolate (151%; mean 38 g; range 25-50 g), each of which represented approximately 1.5 standard AGHE servings.

The findings of the present study indicate that there is variability between parents' and children's estimation of typical portion sizes compared with national recommendations. SO WHAT? Dietary interventions to improve individuals' dietary patterns should target education regarding portion size.