How many Americans does smoking kill each year? If you're going by the surgeon general, the answer is about 480,000. But a new study published in the New England Journal of Medicine suggests the number is actually more like 575,000. The issue is that only 21 causes of death are officially blamed on smoking, the Los Angeles Times explains—think heart disease, stroke, COPD, and certain cancers, including lung and esophageal. But those causes of death actually only account for 83% of deaths among smokers that the study tracked. The rest were caused by things like renal failure, infections, other cancers, and even accidents and suicide, which, the Times notes, "have a more tenuous link to smoking." Researchers looked at five large studies involving nearly a million people to compile the information.
The diseases not officially caused by smoking were more likely to kill current smokers than nonsmokers: Breast cancer was 30% more likely to kill female smokers; prostate cancer was 40% more likely to kill male smokers; smokers were twice as likely to die of infections, hypertension, and certain digestive diseases than nonsmokers—and they were as much as 3.6 times more likely to die of cirrhosis. The comparisons go on, and in some cases, a smoker's risk was even greater the more cigarettes he or she smoked per day. Why? The study didn't actually establish a cause-and-effect relationship, the New York Times notes, but researchers offer explanations: in the case of infections, possibly because smoking hampers the immune system. For intestinal or digestive illnesses, possibly because smoking reduces blood flow to the intestines. The good news? If you quit, the higher risks fade the longer you stay away from cigarettes, Reuters reports. (If you do quit, you may have trouble finding "magic" lozenges.)