Legalization of marijuana expected to increase marijuana use in teens

Legalizing marijuana may prompt some high schoolers to use the substance who otherwise wouldn't, a new study suggests.

Colorado and Washington have started the legalization trend, allowing recreational use of the drug. Currently, 15 states have decriminalized the practice while 19 others - along with the District of Columbia - allow doctors to prescribe medical marijuana.

The study used data from a nationwide ongoing study of the behaviors, attitudes and values of American secondary school students. The results show that a large portion of high school students - 10 percent - who have not before used marijuana would try it if it were legal.

"Our study focused on intention to use and it was the first to find that groups generally not 'at risk' become more 'at risk' when legalized," Dr. Joseph J. Palamar, assistant professor at the Department of Population Health, NYU Langone Medical Center, said in a statement.

As expected, high-risk groups, including males and cigarette smokers, showed increased odds for intent to use marijuana. Not surprisingly, those who already used marijuana would continue to use it often or more often if it were legalized.

Palamar notes that health concerns about marijuana use don't seem to come into play.

"What I personally find interesting is the reasonably high percentage of students who are very religious, non-cigarette smokers, non-drinkers, and those who have friends who disapprove of marijuana use - who said they intended to try marijuana if it was legal," he said. "This suggests that many people may be solely avoiding use because it is illegal, not because it is 'bad' for you, or 'wrong' to use."

Researchers caution that regardless of legal status, as marijuana use increases, it is more important to be aware of possible adverse effects. They noted that public health education for those who intend to use marijuana or who already do would be beneficial, especially given that 64 percent of U.S. young adults, according to the study, are expected to use marijuana in their lifetime.