Wanting More, Seeing Less: Hunger Reduces Calorie Evaluations

Food for thought: Reinforced learning and recall of physical activity calorie equivalent (PACE) and numerical calorie content in an associative learning task

Calorie overconsumption has been proposed as a critical contributing factor to rising obesity rates. To combat this health issue, governments and policymakers have suggested implementing numerical caloric content labels. Alternatively, physical activity calorie equivalent (PACE) labels are being proposed as an easier-to-understand metric, representing the amount of physical activity required to burn off calorie content. This study examined individuals' ability to correctly estimate either the numerical caloric content or the PACE values of food images in an associative learning task. Moreover, it assessed whether this knowledge was learned and retained over time. One hundred and ninety-one participants were instructed to estimate either the numerical caloric content or PACE values of thirty food images. To facilitate learning, feedback on the correct number of calories or PACE values was provided during the first session (Time 1). To assess retention, people re-estimated numerical caloric content or PACE values of the same food pictures three days later (Time 2) and seven days later (Time 3), where feedback was not provided. Results showed that participants in both groups improved their estimations using feedback, with people being consistently more accurate when estimating numerical calorie content. Yet, our results also suggest that participants consolidated their knowledge of PACE values over time. Finally, our findings show that hunger moderates individuals' estimation ability, where hungrier people are less accurate than satiated ones. The results contribute to our understanding of how consumers process, estimate, and learn PACE labels versus numerical caloric content, and provide valuable information for researchers and policymakers to develop and implement nutritional labels as a health strategy.

The impact of nutritional labeling on adult snack choices: A controlled field experiment in a non-commercial professional setting

Each year, 2.8 million people die because of comorbidities associated with being overweight. Snacking substantially contributes to people's calorie intake. One way to nudge consumers towards healthier alternatives is the implementation of nutritional labeling. This study reports on a controlled field experiment that evaluates the effect of two nutritional labels on free snack choices (n = 739). Participants at a conference could choose between nuts, cookies, and candy bars as a snack, presented at the bar at six different locations across 2 bar counters. The labels were set up in front of each snack in three conditions: no labeling (control), a calorie label, or a traffic light label (i.e., the Nutri-Score). The location of the snacks on the counter (Either side of the counter; Center, Right, Left) and the time-of-day (Morning (=reference) vs Afternoon) were statistically controlled for. The results show that calorie labels could not successfully nudge consumers toward healthier snack choices (nuts instead of candy bars or cookies). In contrast, the Nutri-Score label significantly increased the probability of choosing nuts over candy bars. The Nutri-Score also increased the chance of choosing nuts over cookies, but the difference was not significant. No prior studies to our knowledge have directly compared calorie labels to the Nutri-Score. This study suggests that the Nutri-Score label can be a more successful intervention than calorie labels to nudge consumers towards healthier choices in situations were free snacks are offered, like many modern workplaces. Changing snacking behavior is challenging and naturalistic field experiments like this one are needed to translate the theory from previous laboratory studies to real-life settings.