The study shows the damage from even light tobacco smoking is more severe, and associated with a higher risk of premature death, than previously thought. (Agencies)
The four-year analysis of smoking data has found that two-thirds of deaths in current smokers can be directly attributed to smoking, much higher than international estimates of 50 percent.
The study looked at health records from more than 200,000 people participating in the Sax Institute's 45 and Up Study and found current smokers were cutting at least 10 years off their lifespan.
"We all know that smoking is bad for your health, but until now we haven't had direct large-scale evidence from Australia about just how bad it is," said study leader and Scientific Director of the 45 and Up Study, Professor Emily Banks.
"We've been relying on evidence from other countries," said Banks.
With Australian smoking prevalence peaking in 1945 for men and 1978 for women, the country was now experiencing a "mature epidemic" where the full impact of smoking on health is only just being realized, Banks said.
The study found that over the four year follow-up period, current smokers were three times more likely to die than people who had never smoked.
According to study co-author Associate Professor Freddy Sitas from Cancer Council NSW, the risk of dying over the four years of the study increased with the number of cigarettes smoked per day.
"Even among less heavy smokers – those smoking an average of 10 cigarettes per day, the risk of death was more than doubled," Sitas said.
"People don't realize how damaging even light smoking is for your health, for cancer, heart disease, lung disease and a range of other conditions," said Sitas.
"The good news is that stopping smoking at any age reduces the risk; the younger you are when you quit, the better," Banks said.
The study shows the damage from even light tobacco smoking is more severe, and associated with a higher risk of premature death, than previously thought.