Changes in the cigarette consumption of smokers in relation to changes in tar/nicotine content of cigarettes smoked.

Over a 13-year period, 59 per cent of 28,561 smokers decreased the tar and nicotine (T/N) level in the cigarettes they smoked without changing the number of cigarettes smoked to any important extent. On the other hand, more than 54 per cent of the "less than one pack a day" smokers as compared to only 25 per cent of the "one pack or more a day" smokers increased the number of cigarettes smoked. Nicotine dependency plays a minor role in determining the smoking habits of those who continue to smoke on a long-term basis.