A morning light is slightly more lethal. So explain Penn State College of Medicine researchers, who found that smokers who sampled their first cigarette within the first 30 minutes of waking up were more likely to develop lung cancer. Our first thought at this news? Maybe morning smokers were more likely to be frequent smokers. But the researchers, as relayed by BBC News, controlled for amount of cigarettes smoked per day and still noted the trend. Curiously, they explained to the BBC that "Smokers who light up soon after waking tend to smoke each cigarette more intensively." Meaning that more smoke is inhaled into the lungs at this time.
Research hasn't been kind to those who enjoy an early in the day cigarette. In 2007, a review of studies published in the journal Nicotine and Tobacco Research found that morning smokers had a harder time quitting. The paper described these smokers need as "heavy, uninterrupted and automatic smoking" and noted: "it was a valid predictor of a smoker's ability to quit cigarettes and remain tobacco free. The earlier a person smoked the first cigarette, the more difficult it would be for that smoker to quit cigarettes."