Thanks to years of concerted prevention efforts, fewer teens smoke cigarettes, but what about marijuana and e-cigarette use? Unfortunately, those rates are rising. Part of the problem is that, while adolescents got the message about the harmful effects of cigarettes and the manipulative marketing practices used by their makers, when it comes to other products, the message may have been murkier.

A new study published in the Journal of Adolescent Health sought to find out more about adolescents’ knowledge and perceptions of risks of e-cigarettes and marijuana and how these perceptions are formed. Participants described negative consequences of cigarette use but were much less sure regarding risks of marijuana and e-cigarette use. On the other hand, they listed few benefits of cigarettes but named a number of benefits of e-cigarette and marijuana use. Adolescents described learning about these products from the media, from family and friends, and from the school environment.

The study’s authors concluded that teens have learned from multiple sources about risks of using cigarettes, but they receive much less and often incorrect information regarding marijuana and e-cigarettes, likely resulting in their positive and often ambivalent perceptions of marijuana and e-cigarettes.

The study’s lead author, Maria Roditis, PhD, a postdoctoral scholar in adolescent medicine said, “Kids were really good at describing the harmful things that happen with cigarette smoking, but when we asked about other products, there was a lot of confusion.”

“We’re good at delivering messaging that cigarettes are harmful, but we need to do a better job with other products that teens may smoke,” added Bonnie Halpern-Felsher, PhD, professor of pediatrics in adolescent medicine and the study’s senior author. “We don’t want the message kids get to be ‘cigarettes are bad, so everything else might be OK.’”

When it comes to e-cigarettes, these are newer products that some adults may be less familiar with. Or maybe we’ve heard that these products can be helpful for those who want to quit smoking, so we know they can have some benefits. And how about medical marijuana—if it’s safe in some circumstances, does that mean it is a less-harmful substance for teens to try? (By the way, if you’re wondering this, just try substituting “oxycontin” for “marijuana” in that sentence and ask it again.) In other words, maybe adults also lack information or are ambivalent themselves. Unfortunately this lack of communication may sound like tacit approval to teens or at least not DISapproval, and so they may be more likely to give something a try, or assume it “can’t be that bad.” However, e-cigarettes still contain cancer-causing chemicals, and nicotine and can lead to addiction and possibly future cigarette smoking. With their candy-colors and flavors like “unicorn puke” they are clearly being made to appeal to young customers. Marijuana is still an illicit drug that can cause harm, particularly to developing brains. We need to get our message straight, and we need it to be loud and clear: smoking—of any kind—is harmful to your health. Don’t do it.