A new study finds that pod-based vape pens may lead to greater nicotine dependence than other types of e-cigarettes.

The pod-based e-cigarettes have been popular with teenagers and young adults since they came on the market in 2015, but little has been known about their health effects. A new systematic review led by researchers at the Harvard Chan School found that while the products may contain lower levels of harmful ingredients than conventional cigarettes, there is no evidence that even these lower levels are safe for youth.

This is the first paper to synthesize research findings on pod-based e-cigarettes, said first author Stella Lee, formerly a National Cancer Institute Cancer Prevention postdoctoral fellow in the Department of Social and Behavioral Sciences and currently an assistant professor at Konkuk University in South Korea.

“We found that pod-based e-cigarettes have a higher potential to get youth and young adults addicted than other devices,” she said. “To prevent this from happening, we need stronger health communication messages that alert people to these findings.” The study will be published online June 1 in JAMA Pediatrics.

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