Smartphone-based cognitive bias modification training improves healthy food choice in obesity: A pilot study

Obesity is partly driven by unhealthy food choices underpinned by cognitive biases, including approach bias (a tendency to move towards food cues) and delay discounting (a preference for immediate rewards). Cognitive training strategies aimed at modifying these biases, namely, approach-avoidance training (AAT) and episodic future thinking (EFT), may improve food choice. This pilot randomised trial examined the effect of these two trainings, delivered daily for 1 week via smartphone apps, on approach bias for healthy/unhealthy foods, delay discounting for money/food, and hypothetical food choice. Sixty overweight/obese participants (18-45 years) were randomly allocated to AAT, EFT, or control. Outcomes were measured at pretraining, posttraining, and 6-week follow-up. AAT reduced approach bias for unhealthy food and increased healthy food choice. However, EFT did not affect delay discounting or food choice. We conclude that AAT is useful for improving food choice in obesity and that smartphones are a feasible, engaging way to deliver training.