为什么戒烟如此困难

美国“生命无秘密”网站10日报道：为什么戒烟如此困难？吸一口烟能在几秒钟内迅速将微小的尼古丁颗粒送进大脑。随后尼古丁控制了脑细胞受体，并释放出多巴胺——大脑中感觉良好的化学成分，能给人带来愉悦和舒适的感觉。

此外，在过去10年，烟草公司改变了香烟的设计和成分，使它们对第一次吸烟的人更有吸引力，使长期吸烟的人更容易上瘾。变化包括在烟草中加入氨，它将尼古丁变成一种更快达到大脑的形式，并增加了烟嘴中的孔，这使人们能将烟更深地吸入肺部。

Why is smoking so difficult to give up? Inhaling a puff of smoke from a cigarette sends nicotine molecules zooming up into the brain within seconds. Then the nicotine grabs hold of receptors on brain cells and releases dopamine, the brain's feel-good chemical, bringing feelings of pleasure and comfort.

Over the past decade, cigarette companies have made changes to the design and ingredients in cigarettes to make them more alluring to first-time smokers, and more addictive for long-time smokers. These changes include adding ammonia to the tobacco, which converts nicotine into a form that gets to the brain faster, as well as adding holes to cigarette filters that allow people to inhale smoke more deeply into their lungs.
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http://language.globaltimes.cn/bilingual/2010-12/601378.html