Thanks in part to a concerted campaign to alert teens to the dangers of smoking, cigarette use is down in the U.S. Marijuana use? Not so much.

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Seems like teens have gotten the memo that cigarettes are bad for you; however, the same isn’t true for marijuana, according to a study by the Center for Disease Control and Prevention.Released late last week, the government study revealed that in a nationwide study of 15,000 high school students, pot is now more popular among teens than cigarettes, CBS reports. Eighteen percent of surveyed students in 2011 reported smoking a cigarette in the past month, while 23% reported smoking marijuana in the last 30 days.

Perhaps thanks to the anti-smoking campaigns in ads and in schools, or to the personal experiences teens may have with family members or relatives with lung cancer, cigarette use has been on the decline over the past few years.

But apparently, the association of marijuana with cancer and other health risks is not as prevalent among teens. “I just hear a lot of dangers of cancer and cigarettes and I think that’s why a lot of teens look to marijuana,” Tianda, a Philadelphia high school junior who wasn’t identified by her full name, told CBS Philly.

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While plenty of research has been done on the health effects of the marijuana use, results are mixed. A study published in the journal Addiction last year found that marijuana had little long-term effect on learning and memory, and that any cognitive damage was reversible.

However, while there may not be lasting cognitive effects, there could be other health effects. According to the National Institute on Drug Abuse, marijuana smoke contains 50-70% more carcinogenic hydrocarbons than tobacco smoke, and that pot smokers usually inhale more deeply and hold their breath, which can lead to an even larger increase in exposure to the smoke.

But then, the NIDA goes on to report:

Marijuana smokers show dysregulated growth of epithelial cells in their lung tissue, which could lead to cancer; however, a recent case-controlled study found no positive associations between marijuana use and lung, upper respiratory, or upper digestive tract cancers. Thus, the link between marijuana smoking and these cancers remains unsubstantiated at this time.

Teens are going to need some hard and fast facts — and plenty more education — before they believe that pot smoking is as detrimental as cigarettes.

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