Body appearance values modulate risk aversion in eating restriction

Eating decisions depend on both appetitive and social motivation processes but the interactions between these motivations are poorly understood. We examine how women from nonclinical and clinical samples with variable levels of eating restriction make value-based decisions during an experimental task where monetary values are coupled with values related to body appearance, such as the social value of thinness. We show that eating restriction is associated with less risk taking and greater hesitancy when making decisions, but this general tendency is modulated by subjective body-related valuations in both subclinical and clinical samples; risk taking is decreased and hesitancy is increased when monetary reward is coupled with larger body stimuli, particularly in ‘at risk’ samples, and the reverse when reward is coupled with thinner body stimuli, particularly in clinical samples. Computational modelling further indicated that these behaviours are driven by an aversion to risk rather than loss, with desirable body outcomes being associated with less risk aversion, and undesirable body outcomes linked to greater risk aversion. These findings have important implications for current explanations of eating, indicating that cognitive and social factors may influence eating decisions by distinct mechanisms.