Reply #84: That's possible, but people don't quit smoking at random

[Kurt_and_Hunter]

A person might quit because his lungs are starting to feel terrible, if you see what I mean. Or general health failing... immune function declining.

Also, I wouldn't be shocked if nicotine (or even carbon monoxide) actually retards the tumor formation that the tars spur. The reason I say that is that tobacco is the only substance you can set on fire and deeply inhale the smoke fifty times a day for forty years without dying. (Figure heavy smokers start average age 15, 40 years takes them only to 55.)

The mystery of tobacco isn't why it is so dangerous, but why it is so harmless. Smoking toilet paper or oak leaves like that would kill you in a week. (Like an effective virus, tobacco is mild enough to allow you to get killed by it. If it was like smoking newspaper nobody would have ever started.)

So if they found that tobacco smoke simultaneously causes lung cancer and slows its development it wouldn't shock me. (Lungs would probably be a special case, unlike tobacco-caused colorectal, breast, etc.)