Many teens who use smokeless tobacco also smoke cigarettes, according to a national survey of almost 19,000 middle school and high school students.

The survey found 5.6 percent of young people reported using smokeless tobacco, including chewing tobacco, snuff or dip, snus or dissolvable products. Of these teens, about 72 percent said they also smoked cigarettes. Among teens who used only snus or dissolvable products, 81 percent also smoked cigarettes, Reuters reports. Teens with friends and family members who smoked were at highest risk of using both, according to a news release.

Only 40 percent of teens using smokeless tobacco said they had plans to quit.

Public health experts have said snus and dissolvable tobacco products could encourage users to try conventional smokeless tobacco and cigarettes, the article notes.

Lead researcher Dr. Gregory Connolly of the Harvard School of Public Health told Reuters, “We found higher current use than we expected. It’s just not experimentation, it looks like it’s taken hold among adolescents. The most distressing finding was that this is not resulting in children or in young adolescents switching from smoking to these new products that may or may not be safer when used alone. They’re using both in very high numbers.”

The findings are published in Pediatrics.