Two new studies published online in the journal Cancer, sponsored by the American Cancer Society, show that smokers who prefer to smoke their first cigarette shortly after waking up in the morning have a higher risk of developing lung and head and neck cancers than other smokers. The results may help identify smokers who are at particularly high risk of developing cancer, so that targeted smoking cessation interventions can be used to reduce their risk. Smoking increases an individual’s risk of developing various cancers, but why do only a fraction of smokers develop cancer? Joshua Muscat, PhD, of the Pennsylvania State University College of Medicine, and colleagues investigated whether nicotine dependence, characterized by time to first cigarette upon waking, had an effect on the risk of lung and head and neck cancer in smokers independent of frequency and age of smoking. The first lung cancer analysis included 4,775 lung cancer patients and 2,835 controls, all of whom were regular smokers. Compared with those who smoked their first cigarette 60 minutes after waking up, those who smoked their first cigarette between 31 and 60 minutes after waking up had a 31% increased risk of developing lung cancer, while those who smoked their first cigarette within 30 minutes of waking up had a 79% increased risk of developing lung cancer. The second head and neck cancer analysis included 1,055 head and neck cancer patients and 795 controls, all of whom had a history of smoking. Compared with those who smoked their first cigarette 60 minutes after waking up, those who smoked their first cigarette between 31 and 60 minutes after waking up had a 42% increased risk of head and neck cancer, while those who smoked their first cigarette within 30 minutes after waking up had a 59% increased risk of head and neck cancer. Dr. Muscat noted, “These smokers have higher levels of nicotine and other tobacco toxins, and they may be more addicted to smoking than those who can tolerate it for half an hour or more after waking up. It is possible that a combination of genetic and individual factors contribute to more pronounced nicotine dependence.” Such smokers should participate in targeted smoking cessation programs, and appropriate interventions will help reduce the adverse health effects of tobacco. However, the researchers also cautioned that the results of case-control studies may be affected by recall bias, measurement error and confounding factors. Both studies were funded by research grants from the National Cancer Institute and the Pennsylvania Department of Health. The investigators declare no relevant financial conflicts of interest.