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.
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 did not explain the reasons behind the apparent effect.
The study, published in the November issue of the Archives
of Pediatrics & Adolescent Medicine, was based on a 2002
survey of 5,263 Swiss students age 16 to 20, of whom 455
smoked marijuana only, 1,703 who used both marijuana and
tobacco and 3,105 who abstained from both.
The report said that while marijuana use has declined
among U.S. adolescents, it has increased in recent years
among the same age group in Switzerland and other European
The study said that while one theory holds that using
legal drugs like nicotine and alcohol opens the door to
marijuana and other illegal drug use, recent research
also has found marijuana may come first and it "may
reinforce cigarette smoking or lead to nicotine addiction
In the study, about half of the tobacco and marijuana
group had used the latter drug 10 times or more in the
previous month. That compared to 56 percent in the marijuana-only
group who had used the drug only once or twice in the
same time period.
"These findings agree with previous research indicating
that (tobacco) smokers were significantly more likely
to be heavy cannabis users than nonsmokers," the
In addition, those who use only marijuana were less likely
to have started using that drug before the age of 15 compared
to tobacco users, and the tobacco-marijuana group was
more likely to have abused alcohol, the study said.