A new report offers bad news for “social,” or occasional smokers: It doesn’t take much smoking to put you at a significantly higher risk of death.
According to the study, published in JAMA Internal Medicine, people who consistently smoked an average of less than one cigarette per day over the course of their life were 64 percent more likely to die an early death than people who had never smoked.
That figure rose to 87 percent for people who smoked between one and 10 cigarettes per day.
“The results of this study support health warnings that there is no safe level of exposure to tobacco smoke,” Maki Inoue-Choi, Ph.D., the lead author of the study, said in a statement. Inoue-Choi is a staff scientist at the National Cancer Institute’s Division of Cancer Epidemiology and Genetics.
For the study, the researchers analyzed data on over 290,000 adults ages 59 to 82 who participated in a national survey. Participants were asked about their smoking habits during nine different periods across their lifetime, from before they reached their 15th birthday through the time they turned 70.
When looking at cause of death, the researchers found a particularly strong association with smoking and lung cancer mortality. People in the study who consistently smoked an average of less than one cigarette per day over their lifetime had nine times the risk of dying from lung cancer than people who had never smoked. For those who smoked between one and 10 cigarettes per day, the risk of dying from lung cancer was nearly 12 times higher than that of total non-smokers.
The results also showed that people who smoked between one and 10 cigarettes a day had over six times higher risk of dying from respiratory diseases and about one and half times higher chance of dying of cardiovascular disease.
The study has several limitations, including that the participants were mostly white and in their 60’s and 70’s. The researchers said future studies should involve younger populations and other racial and ethnic groups to learn more about the effects of low-intensity smoking.
The study also relied on people recalling their own smoking history over many decades – which could result in inaccurate reporting – and lacked detailed information about people who reported smoking less than one cigarette per day. Therefore, the authors could not compare the effects of smoking every other day, every few days, or weekly.
Still, they say the research provides good evidence that even occasional smoking can be hazardous to your health and that people are much better off if they simply never light up.
“Together, these findings indicate that smoking even a small number of cigarettes per day has substantial negative health effects,” Inoue-Choi said, “and provide further evidence that smoking cessation benefits all smokers, regardless of how few cigarettes they smoke.”