ONE TOKES, THE OTHER DOESN'T

Is Pot Actually a Gateway Drug?

Parents and school principals are always trying to scare kids with the
message that smoking pot will lead to harder drugs. Well, a study in the
Journal of the American Medical Association suggests that the grownups may
be on to something. By tracking 311 pairs of Australian twins (both
fraternal and identical) in which one twin used marijuana before age 17 and
the other did not, researchers have been able to show that early pot users
are as much as five times more likely to use or abuse cocaine, heroin,
hallucinogens, sedatives or alcohol.

This isn't the first study to call pot a gateway drug. What makes this one
so persuasive is that it factors in such things as economic background,
family upbringing and even, in the case of identical twins, genetic makeup.
"We actually were expecting that by using twins, we'd find that the
association between early use and later abuse would disappear," says Michael
Lynskey, a visiting psychiatry professor at Washington University in St.
Louis, Mo., and the study's lead author.

Does marijuana use trigger subtle biochemical changes that encourage
drug-taking behavior? Or does cannabis give kids an entree into social
circles where stronger drugs are used? The study doesn't have all the
answers, but it does offer kids another reason to heed their elders.