Increased brain and behavioural susceptibility to portion size in children with loss of control eating

Summary Background Portion size influences intake (i.e. the portion size effect [PSE]), yet determinants of susceptibility to the PSE are unclear. Objective We tested whether children who reported an episode of loss of control (LOC) eating over the last 3 months would be more susceptible to the PSE and would show differential brain responses to food cues compared with children with no‐LOC. Methods Across five sessions, children ( n  = 47; 7–10 years) consumed four test meals at 100%, 133%, 167% and 200% conditions for portion size and completed a functional magnetic resonance imaging scan while viewing pictures of foods varied by portion size and energy density (ED). Incidence of LOC over the past 3 months was self‐reported. Random coefficient models were tested for differences in the shape of the PSE curve by LOC status. A whole‐brain analysis was conducted to determine response to food cues during the functional magnetic resonance imaging. Results Reported LOC ( n  = 13) compared with no‐LOC ( n  = 34) was associated with increased susceptibility to the PSE, as evidenced by a positive association with the linear slope ( P  < 0.005), and negative association with the quadratic slope ( P  < 0.05) of the intake curve. Children who reported LOC compared with no‐LOC showed increased activation in the left cerebellum to small relative to large portions ( P  < 0.01) and right cerebellum to High‐ED relative to Low‐ED food cues ( P  < 0.01). Conclusion Children who reported LOC were more susceptible to the PSE and showed alterations in food‐cue processing in the cerebellum, a hindbrain region implicated in satiety signalling.