How sweet odors affect healthy food choice: An eye-tracking study

How to make healthy food choices the preferred ones is a public health concern worldwide. A promising way could be to utilize the sensory food cues in the environment, such as odors. Previous studies have shown conflicting results on whether odors can impact food choice, and its underlying mechanism remains unclear. The current study aims to investigate the effect of sweet food odors on food choices. A total of 53 participants were recruited to complete two sessions of different sweet odor exposure: healthy (apple, honey melon) or unhealthy (chocolate, caramel). In each session, the participants were asked to choose from eight (in-)congruent food products (an unhealthy and healthy option for each of the odors) after 10min odor exposure. Visual attention to the food products was measured by Tobii Pro Glasses 2 eye-tracker. Results showed that healthy food products were chosen more frequently regardless of the (healthiness of the) odor exposure. Moreover, participants fixated on all food products for a longer time and more often, and showed a longer time to first fixation on food products during healthy odor exposure compared to unhealthy odor exposure. These findings indicate that healthy odors can prime visual attention and orientation towards both healthy and unhealthy foods. However, this priming does not necessarily lead to congruent food choices, and other cognitive factors likely play a role in the final food decision-making.