Saw this article about the physical addiction of nicotine and cigarettes.
Here's the beginning of the article:
Cigarette addiction is a biological and psychological condition that compels a person to satisfy the need for a particular stimulus (in this case nicotine) and to keep satisfying it, no matter what.
A person with a strong cigarette dependency, one who is addicted to cigarettes or nicotine, has a condition that undermines optimal function and drives that person to compulsively use and abuse nicotine despite the negative consequences.
How can you better understand your cigarette dependency? Consider, for example, your morning cup of coffee. It's a strong dependency or addiction much like your nicotine addiction.
All you have to do is skip your first cup of the day, and you will quickly learn about your body's dependence on caffeine. This does not necessarily mean that you are addicted to caffeine, only that your body wants it, and let's you know with that splitting headache that it expects some coffee, and you're not supplying it.
Read the whole article here:
Cigarette Addiction is Physical