Food approach dynamics in daily life: Speed and force of food approach movements fluctuate with hunger, but less so for people with high BMI.

Abstract

Researchers have suggested that the overconsumption of food, alcohol, and drugs could be explained by chronically elevated approach tendencies to rewarding but unhealthy stimuli. Here, we use the example of food to show that dysregulated rather than chronically elevated approach tendencies are associated with adverse health outcomes. To this end, we developed a new smartphone-based paradigm to measure dynamic changes in food approach tendencies outside the laboratory (piloted with n = 48). We demonstrated in three preregistered experiments (total N = 367) that food approach tendencies decrease from before to after people have eaten. We further show that in overweight and obese participants, these dynamics are disrupted as their food approach tendencies increase rather than decrease after meals. In addition to showing these effects based on traditional reaction time-based food approach tendencies, we also demonstrate these patterns in a novel measure of response force-a measure that has long been used to study motivation in animals but has received little attention in humans. Together, our findings suggest that both reaction time-based and force-based approach tendencies change dynamically in accordance with people's need states and that disruptions in these dynamics are associated with adverse health outcomes, such as overweight and obesity.