Teens’ use of smokeless tobacco products has held steady since 2000, at about 5 percent, a new study finds.

Researchers at the Harvard School of Public Health compared data from the 2000 and 2011 U.S. National Youth Tobacco Survey, according to HealthDay. The 2000 survey included almost 36,000 students, while the 2011 survey included about 19,000. They were asked if they used smokeless tobacco products such as chewing or dipping tobacco or snuff for at least one day within the past month.

The study found a decrease in use of smokeless tobacco among 9- to 14-year-olds, but an increase among those ages 15 to 17, the researchers report in the Journal of the American Medical Association.

The researchers noted the relatively low cost of smokeless tobacco, compared with cigarettes, might make the products more attractive to young people. “The use of modified traditional smokeless tobacco products, such as moist snuff, coupled with lower taxes on smokeless tobacco products [vs. cigarettes] may have contributed to the stable prevalence of smokeless tobacco” at the same time that cigarette smoking has decreased among teens, they wrote.

Under the Family Smoking Prevention & Tobacco Control Act, signed into law in 2009, smokeless tobacco product packages and ads must contain one of four required warnings: the product can cause mouth cancer, the product can cause gum disease and tooth loss, the product is not a safe alternative to cigarettes, and smokeless tobacco is addictive.