Students who smoke marijuana do better in school than their cigarette-smoking classmates, according to a new study.
Canadian researchers surveyed nearly 39,000 Ontario students in grades 7, 9, and 11 between 1981 and 2011 on their marijuana and tobacco use and their academic performance.
The study found that students who only smoked marijuana performed better in school than students who smoked only cigarettes or those who smoked both cigarettes and marijuana.
However, the researchers said their findings reflected the fact that fewer teens smoke today compared to 30 years ago.
Those students who do currently smoke make up a very “marginalized, vulnerable” population, said the study’s lead author, Michael Chaiton, assistant professor in epidemiology and public health policy at the University of Toronto.
“Now there is a distinction between marijuana use and co-use with other substances, and it’s an indication of the changing social norms,” Chaiton said. “So it’s not an absolute that they do better; it’s that social norms have changed and the population of people who use marijuana are more like the general population.”
About 92 percent of tobacco users also smoke marijuana, the researchers found, but only 25 percent of marijuana users also smoke cigarettes.
When the study began in the 1980s, far more students smoked tobacco than marijuana, which few teens used, but that ratio has reversed in the intervening decades.
Researchers said anti-tobacco messages have been effective in cutting smoking rates for young people, but Chaiton said those remaining teen smokers were highly vulnerable to other risky behavior such as vandalism and theft.
“This is not that tobacco is causing this, it is something that has changed socially in the role of tobacco in society,” Chaiton said.
A recent U.S. study found that smoking, the leading cause of preventable death in the country, was largely a habit of poor or working class Americans.
The Canadian study, published in the March edition of the Journal of School Health, found pot smokers performed “relatively” better than cigarette smokers, but they didn’t out-perform non-users.
Chaiton said “people dramatically underestimate the risks associated with cannabis use, particularly among youth,” and he recommended action as decriminalization or legalization efforts spread.
“If we do legalize or change the regulations in dramatic ways, that does change the social environment again and that can, as we’ve seen a number of times, cause big shifts in youth and we could see another big shift in marijuana use among youth,” he said.
[Image: two friends light a cigarette sitting on step via Shutterstock]