Oregon Research Institute, Eugene, OR 97403, USA.
Am J Clin Nutr. 2012 Apr;95(4):810-7. doi: 10.3945/ajcn.111.027003. Epub 2012 Feb 15.
Weight gain leads to reduced reward-region responsivity to energy-dense food receipt, and consumption of an energy-dense diet compared with an isocaloric, low-energy-density diet leads to reduced dopamine receptors. Furthermore, phasic dopamine signaling to palatable food receipt decreases after repeated intake of that food, which collectively suggests that frequent intake of an energy-dense food may reduce striatal response to receipt of that food.
We tested the hypothesis that frequent ice cream consumption would be associated with reduced activation in reward-related brain regions (eg, striatum) in response to receipt of an ice cream-based milkshake and examined the influence of adipose tissue and the specificity of this relation.
Healthy-weight adolescents (n = 151) underwent fMRI during receipt of a milkshake and during receipt of a tasteless solution. Percentage body fat, reported food intake, and food craving and liking were assessed.
Milkshake receipt robustly activated the striatal regions, yet frequent ice cream consumption was associated with a reduced response to milkshake receipt in these reward-related brain regions. Percentage body fat, total energy intake, percentage of energy from fat and sugar, and intake of other energy-dense foods were not related to the neural response to milkshake receipt.
Our results provide novel evidence that frequent consumption of ice cream, independent of body fat, is related to a reduction in reward-region responsivity in humans, paralleling the tolerance observed in drug addiction. Data also imply that intake of a particular energy-dense food results in attenuated reward-region responsivity specifically to that food, which suggests that sensory aspects of eating and reward learning may drive the specificity.
体重增加会导致对高热量食物的奖励区域反应性降低,与等热量、低能量密度的饮食相比,高热量饮食会导致多巴胺受体减少。此外,在反复摄入某种食物后,对美味食物的脉冲式多巴胺信号会减少,这共同表明频繁摄入高热量食物可能会降低纹状体对该食物的反应。
我们检验了这样一个假设,即频繁食用冰淇淋会与对冰淇淋奶昔的接收反应中奖励相关脑区(例如纹状体)的激活减少有关,并研究了脂肪组织的影响和这种关系的特异性。
健康体重的青少年(n=151)在接受奶昔和无味溶液时接受 fMRI 检查。评估了体脂百分比、报告的食物摄入量以及食物渴望和喜好。
奶昔的摄入强烈激活了纹状体区域,但频繁食用冰淇淋与这些奖励相关脑区对奶昔摄入的反应减少有关。体脂百分比、总能量摄入、脂肪和糖的能量百分比以及其他高热量食物的摄入量与奶昔摄入的神经反应无关。
我们的研究结果提供了新的证据,表明频繁食用冰淇淋与人类奖励区域反应性降低有关,这与药物成瘾中观察到的耐受性一致。数据还表明,摄入特定的高热量食物会导致对该食物的奖励区域反应性减弱,这表明进食的感官方面和奖励学习可能会导致这种特异性。