No matter what your age or how long you have smoked, giving up cigarettes is the ticket to a longer life. Consider that just 12 hours after your last cigarette, the carbon monoxide level in your blood returns to normal. A year after you've quit, your risk of heart disease is half that of a smoker's.
The things that lead to nicotine addition are similar to those that cause other substance use addictions, or substance use disorders. Risk factors may include: