People who stop smoking before they reach middle age can shun most of the dangers of developing lung cancer. There are now twice as many Britishers over the age of 50 who are former smokers compared with those who continue to smoke. Over the past four decades, Britain has had the largest reduction in lung cancer in the world.
One of the authors is Sir Richard Doll, professor of medicine at Oxford, whose pioneer study in 1950 established the smoking and lung cancer link. A comparison is made between Professor Richard's study in 1950 and the 1995 study. The first study was concerned with identifying the main causes of the rise in lung cancer, which showed the prevailing role of tobacco. The second study was concerned not just with reconfirming the importance of tobacco but also with assessing the lesser effects of indoor air pollution of some houses.
Because there had been wide-spread cessation of smoking, the 1990 study was able to assess the long-term effects of giving up the habit at various ages. Former smokers, on the other hand, had only a small number of lung cancer cases compared with those who continued to smoke, and the rates dropped dramatically the longer they had stopped smoking. Two thirds of current smokers in Britain want to stop. The extent to which they succeed in doing so will be the chief determinant of the number of deaths caused by tobacco over the next few decades.