Of every $10 spent on healthcare in the U.S., almost 90 cents is due to smoking, a new analysis says.

Using recent health and medical spending surveys, researchers calculated that 8.7 percent of all healthcare spending, or $170 billion a year, is for illness caused by tobacco smoke, and public programs like Medicare and Medicaid paid for most of these costs.

“Fifty years after the first Surgeon General’s report, tobacco use remains the nation’s leading preventable cause of death and disease, despite declines in adult cigarette smoking prevalence,” said Xin Xu from the Centers for Disease Control and Prevention (CDC), who led the study.

Over 18 percent of U.S. adults smoke cigarettes and about one in five deaths are caused by smoking, according to the CDC.

Xu and colleagues linked data on healthcare use and costs from the 2006-2010 Medical Expenditure Panel Survey to the 2004-2009 National Health Interview Survey for a nationally-representative picture of smoking behavior and costs.

Out of more than 40,000 adults, 21.5 percent were current smokers, 22.6 percent were former smokers and 56 percent had never smoked. The researchers used prior data on smoking-related disease and deaths to calculate the proportion of healthcare spending by each person that could be attributed to smoking.

They also adjusted their figures for factors like excess drinking, obesity and socioeconomic status, and calculated the proportion of spending by payer.

In that analysis, 9.6 percent of Medicare spending, 15.2 percent of Medicaid spending and 32.8 percent of other government healthcare spending by sources such as the Veterans Affairs department, Tricare and the Indian Health Service, were attributable to smoking.

Of the $170 billion spent on smoking-related healthcare, more than 60 percent was paid by government sources, they wrote in the American Journal of Preventive Medicine.

Smoking-related healthcare costs affect most types of medical care, said Kenneth Warner at the University of Michigan School of Public Health. “Smoking infiltrates the entire body, through the blood stream, and causes disease in many of the body's organs,” he told Reuters Health in an email.

Along with lung and heart problems, smoking can cause eye disease, skin problems and many cancers including pancreatic and bladder cancer, noted Warner, who was not involved in the new analysis.

“This study shows that, in addition to the human misery it inflicts, (smoking) imposes a substantial burden on the nation's health care institutions, especially those funded by the public's tax dollars,” he said.

The true cost of tobacco use may be even higher, Xu said. His study didn't include medical costs linked to other tobacco products like cigars and chewing tobacco.

In 1964, the Surgeon General gave the first report on smoking and health. Since then, there have been many anti-tobacco efforts, ranging from banning tobacco in workplaces to quit-smoking help lines.

Mass media campaigns can be effective in reducing cigarette use, Xu said. In particular, the CDC’s current “Tips from Former Smokers” campaign is credited with an estimated 100,000 smokers quitting permanently.

The combination of research, publicity, policy and treatment has prevented eight million premature deaths in the U.S. since 1964, according to a 2014 Surgeon General's report. Based on research published this year by Warner and his colleagues, he said, “Almost a third of the increase in adult life expectancy since 1964 is attributable to tobacco control.”

“Smoking kills about 480,000 Americans each year and remains the leading cause of preventable death and disease in the United States. No matter what age, it is never too late to quit,” Xu said.