Pot, Tobacco and Youth

A new study challenges some assumptions about marijuana use by adolescents:

A study of more than 5,000 youngsters in Switzerland has found those who smoked marijuana do as well or better in some areas as those who don't, researchers said Monday.

But the same was not true for those who used both tobacco and marijuana, who tended to be heavier users of the drug, said the report from Dr. J.C. Suris and colleagues at the University of Lausanne.

The study did not confirm the hypothesis that those who abstained from marijuana and tobacco functioned better overall, the authors said.

In fact, those who used only marijuana were "more socially driven ... significantly more likely to practice sports and they have a better relationship with their peers" than abstainers, it said.

"Moreover, even though they are more likely to skip class, they have the same level of good grades; and although they have a worse relationship with their parents, they are not more likely to be depressed" than abstainers, it added.

It did not explain the reasons behind the apparent effect.

The researchers also found that those who smoked tobacco were more likely to be heavy users and that those who started before the age of 15 were more likely to be heavy users and misuse alcohol.

This has been trumpeted as proof that marijuana is harmless (here and here). Surely, its harm is hyped. But, this is one study, it appears to be something of an outlier, and skipping class and worse relationships with parents are not insignificant (I'm not suggesting that corelation is causation.). It would be interesting to see this done in a longitudinal study and to see if the findings hold. Of course it would also be good to see the study replicated.

Arch Pediatr Adolesc Med. 2007;161(11):1042-1047.