While I agree that nicotine is addictive, I do not agree that the more you smoke, the more your body will depend on getting more nicotine.
The "dependence" aspect is highly overrated. For example, a TV commercial shows a young lad jumping into water and floating for a while. The announcer says that eventually you'll have to breathe. Then the swimmer quickly moves above water to get a breath of fresh air. The commercial then claims that if you start smoking, then you will have to continue smoking.
The commercial is aimed at young people who have not smoked yet, in the hope of convincing them not to start.
I do not know how effective such advertising is. But I do know it has a very dark side: It helps convince smokers (especially the newbies) that once you're addicted, you cannot quit.
Another commercial shows a former model for cigarette companies who has done serious damage to her vocal cords through smoking. She says that even though many smokers will lose their vocal cords, they cannot quit.
Again, the aim of the commercial is to convince the young not to start smoking. But it has a bad side effect of spreading the urban myth that nicotine addiction is the same as nicotine dependence. In other words, that once you're a smoker, you're doomed.
It is believing this kind of myth why I smoked for so many years believing I could not quit anymore. I had quit three times before (and always stayed off for a long time, the last time for nine years), but this time I sincerely believed I was stuck with smoking for the rest of my life.
It has now (as I write this) been eight days since I stopped believing this urban myth and quit smoking. Not only was it easy, it was easier than the other three times because I already knew what I was doing (and because of my Buddhist training but this writeup would get too long if I were to get into that here).
Here are my observations on the nature of nicotine addiction. They may apply to other kinds of addiction, but I really do not know as I do not have any personal experience with other drugs.
First, as I already hinted, nicotine addiction does not constitute nicotine dependence. Your body does not need nicotine no matter how long you have been addicted. If it did, stopping nicotine intake would do you physical harm: you would shrink, or die, or blow up, or whatever. But you do not. While trying to break serious addiction to alcohol may in some cases result in delirium tremens, I have never heard of any kind of delirium caused by the lack of nicotine.
So, what is nicotine addiction? Very hard to describe unless you have actually experienced it, but it is sort of a tingling in the chest, a reminder it has been so long since you had your last cigarette (or whatever kind of nicotine intake one is addicted to).
The body contains a timer which goes off after so many minutes/hours (differs from smoker to smoker) since the last intake. Sort of a butler ringing the bell and saying: "Pardon me, Sir, it is time for your next cigarette."
We still have a choice. We can say, "Oh, shut up, Jeeves." Or we jump up and say: "Sir, yes, sir!" Generally, we do the latter. And we generally believe we have no other choice.
But we do! Quitting smoking essentially means saying "Shut up, Jeeves!" That's how most people quit. An even better thing to do is saying, "Thank you, Jeeves, that'll be all." That's how I quit this last time without any problems at all.
Naturally, Jeeves has been well trained, so he will keep coming back several times a day, and say: "Sir, I am very concerned about you. I have reminded you how long you have been without a cigarette and you still have not lit one up." He will then try all kinds of tricks to get you to light up. That's his job! That's what you (and your addiction) have trained him to do.
But Jeeves is a smart fellow. Within 72 hours of your last nicotine intake he will figure out you are no longer interested in smoking, and will quit reminding you.
And that is what nicotine addiction is. It is not dependence. It is Jeeves of your unconscious mind ringing a bell to remind you it is time for another cigarette. He does it gently. He does not cause you pain. He just reminds you and keeps reminding you. What you do then is always your choice: You can light up, which is the most common reaction. You can fight it, which is how most people quit (and often fail). Or you can just acknowledge it for what it is -- a reminder -- and continue doing whatever you are doing knowing that within 72 hours it will be gone forever (or at least until you start again, in which case it will resume immediately).
That said, I really wish our society would stop telling us that nicotine addiction equals nicotine dependence. That may stop some young people from ever starting to smoke, but it sure stops many smokers from quitting when they want to.