Need a few more reasons to quit smoking? A new study by the American Cancer Society (ACS), published in the New England Journal of Medicine, linked more deaths from a variety of illnesses to the bad habit than ever before, Fox News reports.

Today, about 18 percent of American adults smoke. The new ACS study said 480,000 people die from tobacco products every year—60,000 to 120,000 more than previously thought.

For the study, researchers looked at the health information of nearly 1 million Americans age 55 and older over a decade. Scientists compared the number and causes of death from various diseases among three groups: smokers, people who never smoked and former smokers.

Researchers found that death rates were two to three times higher among people who smoked than those who never smoked. Most of these additional deaths were tied to diseases smoking is known to cause, including 12 types of cancer, heart disease and stroke.

Findings showed smokers were also twice as likely to die from many other conditions not previously linked to tobacco use, such as kidney failure, routine infections, cirrhosis of the liver and several additional respiratory diseases. The report also strengthens the evidence that smoking increases the risk of breast and prostate cancers.

Current estimates “have substantially underestimated the burden of smoking on society,” wrote Graham Colditz, MD, PhD, an epidemiologist at Washington University School of Medicine in St. Louis, in the journal’s commentary section.

Colditz added that smokers die, on average, more than a decade before nonsmokers and that cigarettes account for one in five deaths in the United States today.  

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