Abstract: MON 542
Post-Prandial Brain Response to High-Calorie Visual Food Cues Is Greater in Obese Vs. Lean Children
Presenter: Christian Roth
The high prevalence of childhood obesity demands a better understanding of the satiety response to food consumption. We used functional magnetic resonance imaging (fMRI) to characterize brain function related to satiety in children. view more
The high prevalence of childhood obesity demands a better understanding of the satiety response to food consumption. We used functional magnetic resonance imaging (fMRI) to characterize brain function related to satiety in children.
Thirty-four obese (ob BMI z-score 2.16±0.30, age 10.4±0.9 y, mean±SD, 41% female, prior to a behavioral weight loss intervention) and 21 normal weight (nw BMI z-score -0.11±0.47, 10.6±0.9 y, 48% female) children were studied. Subjects underwent an fMRI scan (during which they viewed images of high- and low-calorie foods and non-food objects), then consumed a test meal (33% of estimated daily caloric needs), had a 2nd fMRI scan, and finally had an ad libitum buffet meal to test satiety. Serial measures of subjective appetite were obtained. Mean parameter estimates (high- vs. low-calorie food; with higher values indicating greater activation to high-calorie images) from brain regions involved in satiety processing (ventral and dorsal striatum, amygdala, insula and medial orbitofrontal cortex) were extracted for each subject. A global average of brain activation for each subject was calculated across all regions of interest.
While subjective appetite scores of hunger and fullness changed similarly between groups around the test meal, differences in brain activation were noted between ob and nw children. Prior to the test-meal, there was no group difference in the global average of brain activation across our regions of interest (ob 2.4±25 vs. nw 1.0±24, p=0.85). However, within the ventral striatum ob subjects tended to have greater activation to high-calorie foods compared to nw subjects (7.8±23 vs. -5.2±23, p=0.055). After eating the test-meal, global brain activation was higher in ob vs. nw (7.0±24 vs. -7.3±24, p=0.046). Moreover, across all subjects global brain activation was positively associated with BMI z-score (β=6.9, p=0.02). In regional analyses, significant associations with BMI z-score and brain activation were present in the insula (β=7.3, p=0.03) and dorsal striatum (β=4.8, p=0.04). Obese subjects consumed more calories at the ad libitum buffet (1202±400 vs. nw 771±278 kcal, p<0.0001), however the macronutrient choices and consumption based on percentage of their weight-based estimated daily caloric needs were similar.
In conclusion, post-prandial brain response to high-calorie visual food cues was greater in ob vs. nw children despite similar subjective satiety responses. Activation in specific regions regulating sensory integration and homeostasis (insula) and inhibitory control (dorsal striatum) were positively associated with BMI z-score. These findings suggest that obese children may have a blunted central satiety response in which attention to and motivation for high-calorie foods is not maximally suppressed after eating.