Impulsivity and inhibitory control deficits are associated with unhealthy eating in young adults

Abstract

Heightened impulsivity and inefficient inhibitory control are increasingly recognized as risk factors for unhealthy eating and obesity but the underlying processes are not fully understood. We used structural equation modeling to investigate the relationships between impulsivity, inhibitory control, eating behavior, and body mass index (BMI) in 210 undergraduates who ranged from underweight to obese. We demonstrate that impulsivity and inhibitory control deficits are positively associated with several facets of unhealthy eating, including overeating in response to external food cues and in response to negative emotional states, and making food choices based on taste preferences without consideration of health value. We further show that such unhealthy eating is, for the most part, associated with increased BMI, with the exception of Restraint Eating, which is negatively associated with BMI. These results add to our understanding of the impact of individual differences in impulsivity and inhibitory control on key aspects of unhealthy eating and may have implications for the treatment and prevention of obesity.

Figure 1

Anatomy of a trial in the food-distracter Go/NoGo task. Each trial consisted of a target letter and two flanker food distracters presented for 500 ms, followed by a white screen presented for 1000 ms, for the total response limit of 1500 ms. Participants pressed the space bar to “Go” letters (G, Q, R, S, T; 66% of trials) and inhibited their response to the “NoGo” letter (X; 33% of trials). The food-distracter Go/NoGo task measures the efficiency of inhibitory control in the presence of food cues, as indexed by the number of false alarms on the NoGo trials. A higher number of false alarms indicates a greater deficit in inhibitory control.

Figure 2

The results of the structural equation model investigating the relationships between impulsivity, inhibitory control, eating behavior, and body mass index in healthy young adults (N = 204). Large boxes represent eleven continuous, measured variables of interest, grouped by task or questionnaire (grey blocks). Two nuisance variables (sex and hunger ratings) are represented as small boxes. Blue arrows indicate positive associations (thick arrows: p < .05; thin arrows: p < .07), red arrows indicate negative associations (thick arrows: p < .05; thin arrow: p < .10), and absence of arrows indicates lack of associations (p > .10). BIS-11, Barratt Impulsiveness Scale, Version 11; DEBQ, Dutch Eating Behavior Questionnaire.