Calculating Years Lost, to Men and Women
According to the US Centers for Disease Control (CDC), smoking is the single biggest preventable cause of disease and death in the United States, and in many other countries, too. It's also one of the largest public health threats the world has ever faced, says the World Health Organization (WHO). But how many years are lost, in each person who smokes?
A few different studies have quantified the price smokers pay, in lost years of life.
Mortality of men who smoke: A ground-breaking prospective study involved more than 34,000 male British doctors, recruited in 1951 and tracked over the following five decades. The results: long-term smokers died about ten years younger than similar men who had never smoked. Led by Richard Doll, a professor of medicine at Oxford University in the United Kingdom, the study's 50-year results were published in the British Medical Journal in 2004.
Mortality of women who smoke: A 2012 review published in The Lancet examined the mortality cost of smoking on more than a million women in the United Kingdom over a 12-year period. Led by epidemiologist Kirstin Pirie (also of Oxford University), the team writes that it wasn't until the early 21st century that the full effects of long-term smoking could be assessed in women, because heavy tobacco use peaked so much later for them, compared with men.
Pirie's team found that among the almost 1.2 million women studied, those who continued to smoke throughout their lives lost an average of about 11 years of lifespan, when compared with similar women who'd never smoked.
In each review, the primary causes of death were directly related to tobacco use, and included lung cancer, respiratory conditions like chronic obstructive pulmonary disease (COPD), and heart disease, among others. The Centers for Disease Control state unequivocally that smoking causes death; these study findings indicate causation, not simple correlation between tobacco and earlier mortality.
While the dangers of smoking are immense, the benefits of quitting are also substantial. Each of these studies, like many others, have suggested that the risks of tobacco use diminish, the earlier a smoker quits. For example, both investigations found that if a smoker stops before the age of 30, almost all (97% for women) of the excess mortality caused by smoking is eliminated. Quitting before the age of 40 reduced the excess mortality by 90% in Pirie's study, and gained men an extra 9 years of life in Doll's review. Even men who quit smoking at age 60 gained 3 years of additional life span when compared to male physicians who continued to smoke.
Women quitting as late as the age of 54 were able to avoid about two-thirds of the excess mortality experienced among smokers who stuck with their habit.
Doll R, Peto R, Boreham J, Sutherland I. Mortality in relation to smoking:
50 years’ observations on male British doctors. BMJ 2004; 328: 1519–27.
Kirstin Pirie, Richard Peto, Gillian K Reeves, Jane Green, Valerie Beral, “The 21st century hazards of smoking and benefits of stopping: a prospective study of one million women in the UK.” The Lancet. Published online October 27, 2012.
The Burden of Tobacco Use. US Centers for Disease Control Public Information Sheet. Accessed November 12, 2012.
Tobacco. World Health Organization Fact Sheet. Accessed November 12, 2012.