Two thirds of Australian smokers will be killed by their habit unless they are able to quit, according to a new study from the Australian National University.
The research, which was published in the international journal BMC Medicine, found smoking just 10 cigarettes a day doubled the risk of dying prematurely and that on average, smokers died 10 years earlier than non-smokers.
ANU researcher Professor Emily Banks 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.
"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 assessed the health outcomes of more than 200,000 people who participated in a program coordinated by the Sax Institute in Sydney.
Professor Banks said Australians should be proud of reducing smoking rates to just 13 per cent of the population – a world leading result – despite around 2.7 million people continuing to smoke.
The report found 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.
"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."
The report also found mortality rates among heavy smokers were even higher.
"Mortality rates approximately doubled in those smoking around 10 cigarettes per day and four to five-fold those of never-smokers in current smokers of 25 or more cigarettes per day," the report said.
The survey demonstrated continuing harms of smoking despite tobacco control measures and the need for continuing attention and controls.
"The introduction of plain packaging for cigarettes in Australia in 2012 is an example of the continuing efforts required," the review said.
Despite the alarming findings, the chief executive of Heart Foundation Kerry Doyle said the government was driving down smoking rates through tax increases and plain packaging.
"Higher tobacco prices have been shown to be the most effective intervention available to governments to reduce demand for tobacco," she said.
"With smoking being a major cause of cardiovascular disease, including heart attack, stroke and peripheral vascular disease the more deterrents people have between them and smoking, the better."
The Cancer Council's tobacco control manager, Scott Walsberger, said it was never too late to stop smoking "no matter what your age or how much you smoke".
"People often underestimate the urgency for quitting and many are not aware of how damaging even light smoking is for cancer and other preventable illnesses," he said.
Public Health Association of Australia president Mike Daube said the report demanded a strategic rethink and a ban on all tobacco industry promotion, including lobbying and public relations.
"If anything else caused that death toll it would be seen as a national catastrophe," he said.
"Australia is a global leader, but 1.8 million deaths – 7.5 per cent of the Australian population – demands a different level of action
"We need a clear plan from governments to reduce that toll to an absolute minimum – further tobacco tax increases, strong mass media campaigns, protection for non-smokers and support for disadvantaged groups."
