The study conducted at Australian National University found that smoking as few as 10 cigarettes a day doubled the risk of dying early by as much as 10 years, on average, compared to non-smokers.
The research was published in the international journal BMC Medicine.
Professor Emily Banks from ANU said the study was “a huge wake up for Australia”.
“We knew smoking was bad but we now have direct evidence from Australia that shows it is worse than previously thought,“ she said. “Our findings show that up to two in every three of these smokers can be expected to die from their habit if they don’t quit and this highlights the importance of staying the course on tobacco control.”
The four-year study involved more than 200,000 people whose health outcomes were assessed in a program coordinated by the Sax Institute in Sydney.
Ms. Banks said Australians should be proud of reducing smoking rates to just 13 per cent of the population, despite around 2.7 million people continuing to smoke.
The average duration of a smoking habit was 38.5 years, with the majority smoking for more than 35 or more years, consuming at least 15 cigarettes a day, the study found.
“In Australia, male and female smokers were estimated to have the same risks of death 9.6 and 10.1 years earlier than 75-year-old non-smokers, respectively,” the report said. “Death rates in current smokers were around three times those of people who had never smoked, in both men and women. On average, smokers died around 10 years earlier than non-smokers, over the ages examined.”