Lead author Purnima Kumar, an oral surgeon and professor of dentistry at Ohio State University, and her team were originally interested in studying how our mouth’s microbiome bounces back when someone quits smoking.

These volunteers included people who had vaped for at least 4 months, smokers, people who had stopped smoking and were now vaping, people smoking and vaping at the same time, and a control group that did neither.

The changes the team found seem unique to vaping, and they might even be more potent than what we see with smoking.

In both former smokers who switched to vaping as well as dual users, their microbiomes more resembled those from people who only vaped.

In later experiments using fake mouths, they also found evidence these changes happened even from vaping aerosol without nicotine.

For one, they largely only studied people using older-generation modifiable vaping devices, as opposed to the simpler pods popularized by Juul.

Kumar doesn’t discount the potential of e-cigarettes as a way to help people quit smoking, so long as they’re used temporarily.

But if you’re simply using e-cigarettes to quit smoking, you’re not going through cessation,” she said