A National Cancer Center (NCC) research team has found that exposure to e-cigarette advertisements in retail stores, on the internet and social media, can increase e-cigarette use by 1.5 times among young adults worldwide.

The team, led by Professor Myung Seung-kwon of the Department of Cancer AI & Digital Health at the NCC Graduate School of Cancer Science and Policy, concluded so after conducting a meta-analysis of seven prospective cohort studies published in international journals from 2017 to 2021.

The majority of the 25,722 participants that the team analyzed were young adults in their 20s and 30s, and those exposed to e-cigarette advertising were 1.53 times more likely to become e-cigarette users compared to those not exposed.

Subgroup meta-analyses showed that young adults were 2.2 times more likely to become e-cigarette users when exposed to advertising in retail stores, and 1.5 times more likely to become e-cigarette users when exposed to ads on the internet and social media.

"Since e-cigarettes first became available in China in 2004, e-cigarette companies have invested heavily in e-cigarette advertising on TV, radio, internet, and social media to target potential e-cigarette users, claiming that e-cigarettes are less harmful to health than conventional tobacco and can help people quit smoking," Professor Myung said. "Until recently, studies have shown that exposure to e-cigarette advertisements increases the probability of e-cigarette use, but some studies have also reported no association, so there was a need for a meta-analysis that synthesizes individual studies to determine if and how much exposure to e-cigarettes advertisements increases e-cigarette use."

The team's study showed that exposure to e-cigarette advertisements in retail stores, on the internet and social media, is associated with an approximately 1.5-fold increase in the likelihood of e-cigarette use among adolescents and young adults, Myung added.

Myung said the study is significant because it is the first meta-analysis of this topic globally.

"The use of e-cigarettes, especially among adolescents and young adults, is a trigger for smoking initiation, so stricter regulations on e-cigarette advertisements in retail stores and on the internet and social media are needed," Myung said.

NCC President Seo Hong-gwan also said, "E-cigarette companies claim that e-cigarettes are less harmful than regular cigarettes, but the World Health Organization (WHO) has found that nicotine in e-cigarette smoke adversely affects brain development in children and adolescents, leading to learning disabilities and anxiety."

While additional long-term studies are needed to determine the risk of cancer, e-cigarettes, which contain several carcinogens such as formaldehyde, cannot be considered safe, and their advertising and marketing should be strictly regulated, just like tobacco cigarettes, Seo added.

The results of the research were published in the May 2023 issue of Nicotine and Tobacco Research.