Compelling New Evidence on the Benefits of Quitting Smoking
You've heard plenty about the health benefits of quitting smoking. Now British researchers have provided more compelling evidence of just how significant those benefits can be.
Researchers at Oxford University found that people who quit smoking before age 35 can reduce their risk of developing lung cancer by more than 90%. And giving up smoking even late in life eliminates most of the risk.
While previous studies of quitting have shown the effect on lung cancer rates can be dramatic, the Oxford report in Saturday's British Medical Journal (http://www.bmj.com) gives the clearest evidence yet.
The project, led by Sir Richard Peto, also provides the first prediction of the number of tobacco-related deaths that will occur worldwide in the next 100 years if smoking patterns persist--1 billion deaths, contrasted with 100 million in the last century.
Peto's research found there already are 1 billion smokers in the world and that, by 2030, another billion or so young adults will have started to smoke. If current smoking patterns continue, tobacco-related deaths worldwide will rise from 4 million a year now to about 10 million a year around 2030, an increase of about 100 million a decade, he estimated.
If trends continue, he predicted that about 15% of all adult deaths worldwide in the second half of the 21st century will be due to tobacco.
No matter how early in life a smoker quits, some of the damage done is irreversible and the risk of lung cancer never declines to normal. Recent research has shown that starting smoking before age 18 is particularly harmful to the lungs.
The Oxford study found that only 2% of those who quit by age 30 developed the disease by age 75, compared to a 0.4% chance for people who have never smoked. It also found that 10% of those who quit at 60 will die of lung cancer, and that continuing to smoke into old age results in a 16% risk