New research suggests that if you've quit smoking and switched to vaping, your chances of developing lung cancer won't decrease as significantly as if you had quit nicotine altogether. This conclusion comes from a major population-based study led by Dr. YeonWook Kim, an assistant professor of pulmonary and critical care medicine at Seoul National University Bundang Hospital in Seongnam, South Korea.

Dr. Kim presented the findings at the annual meeting of the American Thoracic Society in San Diego. He emphasized that this is the first extensive study to show the increased risk of lung cancer in e-cigarette users who have stopped smoking.

The study monitored over 4.3 million South Koreans who enrolled in the National Health Screening Program between 2012-2014 or 2018, with follow-up data collected in 2021. Participants were divided into groups based on their smoking and vaping habits. During the follow-up period, more than 53,000 participants developed lung cancer, and 6,351 died from the disease.

Kim's team discovered that individuals who had quit smoking for five years or more but continued vaping still had higher odds of fatal lung cancer compared to those who quit smoking entirely. For those who had quit smoking for less than five years, switching to vaping increased the risk of developing lung cancer or dying from it compared to those who quit without taking up vaping. This trend was particularly evident among people aged 50 to 80.

The study's findings suggest that the potential harms of using e-cigarettes as an alternative to smoking must be considered when developing smoking cessation interventions aimed at reducing lung cancer risk. "Our results indicate that when integrating smoking cessation interventions to reduce lung cancer risk, the potential harms of using e-cigarettes as an alternative to smoking must be considered," Dr. Kim concluded in a meeting news release.

Since these findings were presented at a medical meeting, they should be considered preliminary until published in a peer-reviewed journal.