Switching from paper cigarettes to e-cigarettes fails to lower lung cancer risk

Jul 01, 2026, 09:55 am

A large-scale population-based study has confirmed that smokers who switch to e-cigarettes fail to sufficiently lower their risk of developing lung cancer.

The study revealed that even after quitting conventional cigarettes, continuous e-cigarette use leads to a higher risk of lung cancer incidence and mortality compared to complete tobacco cessation. This finding provides a pivotal new baseline for public health policy and public perceptions of smoking.

According to Seoul National University Bundang Hospital on the 1st, a research team led by Professor Kim Yeon-wook of the Department of Pulmonology tracked 4,524,895 Korean adults with a history of conventional smoking to investigate the association between e-cigarette use, lung cancer incidence, and mortality. The findings were published in the international medical journal Nature Medicine.

The researchers conducted a follow-up analysis totaling 24,182,543 person-years by linking 2018 national health screening data with health records from 2012 to 2014. A population-wide analysis of this magnitude is globally rare among studies evaluating the long-term health impacts of e-cigarettes.

The study showed that individuals who quit conventional cigarettes but used e-cigarettes daily faced a 1.56 times higher risk of developing lung cancer and a twofold higher risk of lung cancer death compared to complete quitters. While the group that continued smoking conventional cigarettes exhibited the highest risk metrics—1.78 times for incidence and 2.41 times for mortality—the risk reduction for those who transitioned to e-cigarettes remained marginal compared to total abstinence.

The risk gap widened even further among high-risk demographics with a history of heavy smoking. For individuals aged 50 to 80 with a cumulative lifetime smoking history of 20 pack-years or more, e-cigarette users experienced a 1.91 times higher risk of lung cancer incidence and a 1.92 times higher risk of mortality compared to those who achieved complete cessation.

The research team explained that while e-cigarettes may reduce exposure to some harmful chemicals generated during the combustion of conventional tobacco, they do not completely eliminate exposure to known carcinogens such as formaldehyde. They emphasized that to effectively mitigate the risk of smoking-related diseases like lung cancer, individuals must entirely halt the use of all tobacco products rather than simply substituting one form for another.

"Many individuals mistakenly believe they have quit smoking after switching to e-cigarettes, but e-cigarette use is still a form of tobacco consumption," Professor Kim stated. "To decisively lower the risk of lung cancer, total cessation—completely giving up both conventional and electronic cigarettes—remains the most effective path."

Park Jun-sung

#Cancer #Cigarette