Abstract
Previous research shows that increased portion sizes distort individual’s estimation of fullness (Expected Satiation), causing inaccurate judgement of food intake (Expected Intake). This phenomenon, in turn, leads to over-consumption and food waste. An interventive strategy is to provide portion size information through portion labelling. An extensive amount of research has focused on testing the effectiveness of portion labelling presented in Words format (e.g. “large”, “400g”), yet little is known about the effectiveness of portion labelling based on Food Images or 3D Models. The present research systematically assesses the effectiveness of portion labelling formats with two empirical studies involving a large cohort of participants. In Study 1, 73 participants rated Expected Intake and Expected Satiation for two dishes (penne and spaghetti) of three sizes (400, 600, and 800g), with each size presented in three different formats of food cues. Further, Study 2 assessed actual pasta intake of the same cohort of participants, over three ad libitum sessions across 7 weeks. Expected Intake error of each label format was quantified by computing differences between a person’s Expected Intake and Actual Intake. Overall, results from these studies found that visual formats (Food Images and 3D Models) yielded higher Expected Satiation and Expected Intake compared to the Words format. However, the Expected Intake error for visual formats (Food Images and 3D Model) was significantly lower than Words format. Overall, present findings suggest that portion labelling based on visual formats facilitates people’s estimation of food intake and therefore helps to alleviate overconsumption and food waste.