Oregon Research Institute, Eugene, OR 97403, USA.
Am J Clin Nutr. 2013 Jun;97(6):1188-94. doi: 10.3945/ajcn.112.055285. Epub 2013 Apr 17.
Obese compared with lean individuals show greater attention-, gustatory-, and reward-region responsivity to food cues but reduced reward-region responsivity during food intake. However, to our knowledge, research has not tested whether an objectively measured caloric intake is positively associated with neural responsivity independent of excess adipose tissue.
We tested the hypothesis that objectively measured energy intake, which accounts for basal needs and the percentage of body fat, correlates positively with the neural response to anticipated palatable food intake but negatively with a response to food intake in healthy-weight adolescents.
Participants (n = 155; mean ± SD age: 15.9 ± 1.1 y) completed functional magnetic resonance imaging scans while anticipating and receiving palatable food compared with a tasteless solution, a doubly labeled water assessment of energy intake, and assessments of resting metabolic rate and body composition.
Energy intake correlated positively with activation in the lateral visual and anterior cingulate cortices (visual processing and attention), frontal operculum (primary gustatory cortex) when anticipating palatable food, and greater striatal activation when anticipating palatable food in a more-sensitive region of interest analysis. Energy intake was not significantly related to neural responsivity during palatable food intake.
Results indicate that objectively measured energy intake that accounts for basal needs and adipose tissue correlates positively with activity in attentional, gustatory, and reward regions when anticipating palatable food. Although hyperresponsivity of these regions may increase risk of overeating, it is unclear whether this is an initial vulnerability factor or a result of previous overeating. This trial was registered at clinicaltrials.gov as NCT01807572.
与瘦人相比，肥胖者对食物线索的注意力、味觉和奖励区域反应更强，但在进食过程中奖励区域反应减弱。然而，据我们所知，研究尚未测试过是否可以通过客观测量的卡路里摄入量与多余脂肪组织无关的情况下，与神经反应性呈正相关。
我们测试了这样一个假设，即客观测量的能量摄入量（考虑到基础需求和体脂肪百分比）与对预期美味食物摄入的神经反应呈正相关，但与健康体重青少年的食物摄入反应呈负相关。
参与者（n=155；平均年龄±标准差：15.9±1.1 岁）在期待和接受美味食物与无味溶液时完成了功能磁共振成像扫描，同时还进行了双标记水能量摄入评估以及静息代谢率和身体成分评估。
能量摄入量与外侧视觉和前扣带皮质（视觉处理和注意力）、额回（初级味觉皮层）在期待美味食物时的激活呈正相关，并且在更敏感的兴趣区域分析中，当期待美味食物时，纹状体的激活也更大。能量摄入量与美味食物摄入期间的神经反应性没有显著相关性。
结果表明，客观测量的能量摄入量（考虑到基础需求和脂肪组织）与期待美味食物时注意力、味觉和奖励区域的活动呈正相关。虽然这些区域的高反应性可能会增加暴饮暴食的风险，但尚不清楚这是初始脆弱性因素还是先前暴饮暴食的结果。该试验在 clinicaltrials.gov 上注册为 NCT01807572。
