Food portion size and energy density evoke different patterns of brain activation in children

Abstract

Background: Large portions of food promote intake, but the mechanisms that drive this effect are unclear. Previous neuroimaging studies have identified the brain-reward and decision-making systems that are involved in the response to the energy density (ED) (kilocalories per gram) of foods, but few studies have examined the brain response to the food portion size (PS). Objective: We used functional MRI (fMRI) to determine the brain response to food images that differed in PSs (large and small) and ED (high and low). Design: Block-design fMRI was used to assess the blood oxygen leveldependent (BOLD) response to images in 36 children (7-10 y old; girls: 50%), which was tested after a 2-h fast. Pre-fMRI fullness and liking were rated on visual analog scales. A whole-brain cluster-corrected analysis was used to compare BOLD activation for main effects of the PS, ED, and their interaction. Secondary analyses were used to associate BOLD contrast values with appetitive traits and laboratory intake from meals for which the portions of all foods were increased. Results: Compared with small-PS cues, large-PS cues were associated with decreased activation in the inferior frontal gyrus (P , 0.01). Compared with low-ED cues, high-ED cues were associated with increased activation in multiple regions (e.g., in the caudate, cingulate, and precentral gyrus) and decreased activation in the insula and superior temporal gyrus (P , 0.01 for all). A PS 3 ED interaction was shown in the superior temporal gyrus (P , 0.01). BOLD contrast values for high-ED cues compared with low-ED cues in the insula, declive, and precentral gyrus were negatively related to appetitive traits (P , 0.05). There were no associations between the brain response to the PS and either appetitive traits or intake. Conclusions: Cues regarding food PS may be processed in the lateral prefrontal cortex, which is a region that is implicated in cognitive control, whereas ED activates multiple areas involved in sensory and reward processing. Possible implications include the development of interventions that target decision-making and reward systems differently to moderate overeating.Am J Clin Nutr 2017;105:295-305.

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

“…For ED, the main effects overlapped with what has been previously reported, with significant differences in response to High‐ED vs. Low‐ED foods in the fusiform gyrus, cerebellar declive, medial frontal and superior temporal gyrus. As these effects have been previously reported , they will not be discussed further in the current paper.…”

“…We previously reported on the main effects of portion size and ED in the first 36 children from this cohort , so these results will not be reported in detail here. However, because we had a larger sample size in the present study, we ran those contrasts again with the updated sample and found additional main effects of portion size in the left lingual gyrus (large portion > small portion; [ F df 1, 48 = 37.76; P < 0.01]) and superior temporal gyrus (small portion > large portion; [ F df 1, 48 = 15.43; P < 0.01]).…”

Dietary energy density: Applying behavioural science to weight management

“…; English et al . ). Longitudinal studies are needed that examine how individual differences in response to food energy density affect bodyweight.…”

“…It makes sense to rely on previous experience (Stubbs & Whybrow 2004); however, when the sensory properties of foods are dissociated from the energy density, expectations and previous experiences with foods can provide unreliable guidance to consumers on amounts to eat (Hogenkamp et al 2012). To understand further what affects food choices, some current research aimed to use functional magnetic resonance imaging to determine how energy density affects brain responses and whether individual variation in responsivity is related to eating behaviour and bodyweight (Fearnbach et al 2016;English et al 2017). Longitudinal studies are needed that examine how individual differences in response to food energy density affect bodyweight.…”

Food or money? Children's brains respond differently to rewards regardless of weight status

“…Functional magnetic resonance imaging studies have shown positive correlations between viewing palatable food stimuli and blood-oxygen-leveldependent (BOLD) response in regions implicated in reward and inhibitory control (10)(11)(12). Alterations in these responses have been positively linked to weight gain (13,14) and obesity in adults (15)(16)(17) and children (18,19).…”