Gone in a puff of smoke

If we assume that we each cross four streets a day on average, then the probability of being killed on any one crossing is 1 in 325,200 - far worse than winning first prize in the lottery. Still, the rationalisation trips easily off the tongue.

The most famous study examining the risks of smoking is Richard Doll's study of 34,439 British male doctors, which he commenced in 1951. This year he published his 50-year follow-up in the British Medical Journal. He concluded that up to two-thirds of the continuing smokers in his study had died from diseases caused by smoking, on average about 10 years younger than lifelong non-smokers.

But his study had some important good news too: that if you stopped smoking at age 60, 50, 40, or 30, then you gained, respectively, about three, six, nine, or 10 years of life expectancy.

About 19,000 smokers in Australia die each year from smoking-related diseases, about 4200 before retirement age.

That's more than all deaths from road injury, alcohol, illicit drugs, skin cancer, suicide, and breast cancer combined.

If a person smokes 18 cigarettes a day for 40 years, they deep baste their lungs with the toxic smoke from 262,980 cigarettes. A cigarette typically takes 5.6 minutes to smoke. If you add up all the time they spend smoking it comes to 1023 solid days or 2.8 years smoking.

Doll's research shows that the average lifetime smoker loses 10 years of life. So next time you suck on a cigarette, ponder that the time it takes you to smoke it takes more than 350 per cent of that time off your life.

Quitting smoking is the single most important thing anyone can do to improve their health. There are now many more ex-smokers in the community than smokers. This holiday season is a great time to join them.