Cigarette smoking is known to cause more than 20 types of cancer as well as other diseases, but the effects of low-intensity smoking (10 or fewer cigarettes per day) have not been well studied.
Maki Inoue-Choi, Ph.D., M.S., R.D., Neal Freedman, Ph.D., M.P.H., and colleagues showed that among 290,215 adults in the National Institutes of Health-AARP Diet and Health Study, current smokers who had smoked less than 1 cigarette per day over their lifetime had 1.64 times higher mortality risk and smokers who had smoked 1 to 10 cigarettes per day had 1.87 times higher mortality risk than never smokers. Risks were lower among former smokers compared to those who continued to smoke and fell with earlier age at quitting.
These results provide further evidence that there is no safe level of exposure to tobacco smoke and that even low-intensity smokers benefit from cessation.
Inoue-Choi M, Liao L, Reyes-Guzman C, et al. Association of long-term low-intensity smoking with all-cause and cause-specific mortality in the NIH-AARP Diet and Health Study. JAMA Internal Medicine 2016. DOI: 10.1001/jamainternmed.2016.7511