Study Finds E-Cigarettes May Reduce Health Benefits of Quitting Smoking

A new study published in the medical journal Nature Medicine reveals that switching from traditional cigarettes to e-cigarettes may not fully eliminate smoking-related health risks. Researchers analyzed data from over 4.5 million former smokers in South Korea and found that those who quit smoking but continued using e-cigarettes had a 56% higher risk of lung cancer and a 22% higher risk of death from any cause compared to those who quit smoking without using e-cigarettes.

The study showed that while quitting smoking generally reduces lung cancer risk by 44% and mortality risk by 37%, these benefits were significantly diminished among e-cigarette users, with only a 12% reduction in lung cancer risk and 23% reduction in mortality. The researchers controlled for factors such as recent quitting, smoking intensity, and baseline health status, and the results remained consistent.

Importantly, the increased risks were observed even in individuals who had quit smoking more than five years prior, suggesting that e-cigarette use may weaken the protective effects of smoking cessation over the long term. However, the study does not prove that e-cigarettes directly cause lung cancer but indicates they may promote cancer progression or maintain harmful biological processes.

Additional research cited includes a comprehensive review linking e-cigarette vapor exposure to early biological changes associated with cancer development, such as DNA damage and chronic inflammation. Another study published in the American Journal of Ophthalmology found that former smokers who switched to e-cigarettes had a 24% higher risk of diabetic retinopathy and increased risks of other serious eye diseases compared to those who fully quit nicotine.

Experts recommend that e-cigarettes be used only as a temporary aid in quitting smoking, with the ultimate goal of complete nicotine cessation supported by proven behavioral and pharmacological treatments. The World Health Organization’s existing guidelines remain unchanged, emphasizing that e-cigarettes should not be considered a safe long-term alternative to smoking.

Summary: A large South Korean study finds that former smokers who continue using e-cigarettes face higher risks of lung cancer and death than those who quit nicotine entirely, suggesting e-cigarettes may reduce the health benefits of quitting smoking. Additional research links e-cigarette use to increased risks of eye diseases, reinforcing calls for cautious, temporary use only during smoking cessation.