Those who do can free themselves if motivated to do so - 35 million have quit cigarettes, which some clinicians regard as more addictive than heroin.
"Allison and I get you two to quit cigarettes, and the next thing we know you're sucking on some other burning carcinogen."
Can caretaker Ramsay quit cigarettes to keep his job?
Furthermore, about 100 of Beth Israel's employees have quit cigarettes for good.
It's not nearly as hard as quitting cigarettes.
A few months ago, he quit cigarettes because he was worried about living long enough to see his grandchildren.
Patience has not become a virtue of mine since I quit cigarettes, so I went for the more convenient option 3.
Quitting cigarettes - and staying smoke-free - helped, the study shows.
She notes that men who quit cigarettes for nine or more years were about as likely as lifelong nonsmokers to get root canals.
Breaking the habit, something few new users consider when they experiment with the drug, is unlike stopping cocaine or quitting cigarettes.