John B Pierce Laboratory, New Haven, CT 06519, USA.
Am J Clin Nutr. 2013 Jan;97(1):15-22. doi: 10.3945/ajcn.112.043307. Epub 2012 Dec 12.
Smoking cessation is often followed by weight gain. Eating behaviors and weight change have been linked to the brain response to food, but it is unknown whether smoking influences this response.
We determined the influence of smoking status (smokers compared with nonsmokers) on the brain response to food in regions associated with weight changes in nonsmokers.
In study 1, we used functional MRI (fMRI) to identify regions of the brain associated with weight change in nonsmokers. BMI and the brain response to a milk shake, which is a palatable and energy-dense food, were measured in a group of 27 nonsmokers (5 men). Sixteen subjects (3 men) returned 1 y later for BMI reassessment. The change in BMI was regressed against the brain response to isolate regions associated with weight change. In study 2, to determine whether smokers showed altered responses in regions associated with weight change, we assessed the brain response to a milk shake in 11 smokers. The brain response to a milk shake compared with a tasteless control solution was assessed in 11 smokers (5 men) in comparison with a group of age-, sex- and body weight-matched nonsmokers selected from the pool of nonsmokers who participated in study 1.
The response in the midbrain, hypothalamus, thalamus, and ventral striatum was positively associated with weight change at the 1-y follow-up in 16 nonsmokers. Compared with nonsmokers, smokers had a greater response to milk shakes in the hypothalamus.
Smokers display an altered brain response to food in the hypothalamus, which is an area associated with long-term weight change in nonsmokers.
戒烟后通常会出现体重增加。饮食行为和体重变化与大脑对食物的反应有关，但尚不清楚吸烟是否会影响这种反应。
我们旨在确定吸烟状况（吸烟者与不吸烟者相比）对不吸烟者体重变化相关脑区对食物反应的影响。
在研究 1 中，我们使用功能磁共振成像（fMRI）来识别不吸烟者体重变化相关的脑区。我们在一组 27 名不吸烟者（5 名男性）中测量了 BMI 和对奶昔的大脑反应，奶昔是一种美味且高热量的食物。16 名受试者（3 名男性）在 1 年后返回进行 BMI 重新评估。体重指数的变化与大脑对奶昔的反应进行回归，以分离与体重变化相关的区域。在研究 2 中，为了确定吸烟者在与体重变化相关的区域是否表现出不同的反应，我们评估了 11 名吸烟者对奶昔的大脑反应。我们比较了 11 名吸烟者（5 名男性）对奶昔与无味对照溶液的大脑反应，这些吸烟者选自参与研究 1 的不吸烟者中，年龄、性别和体重匹配的一组不吸烟者。
在 16 名不吸烟者中，中脑、下丘脑、丘脑和腹侧纹状体的反应与 1 年随访时的体重变化呈正相关。与不吸烟者相比，吸烟者对奶昔的反应更大，尤其是在下丘脑。
吸烟者对食物的大脑反应在下丘脑发生改变，而下丘脑是不吸烟者长期体重变化相关的区域。
