By CBS News Staff
(CBS/AP) Teens who smoke marijuana frequently are more likely to experience a long-term drop in their IQ, according to a new study.
That could be a potential pitfall for millions of teens, given recent estimates show about one in 10 teens in grades nine through 12 smoke marijuana at least 20 times per month. The researchers however didn't find the same IQ dip for people who became frequent users of pot after 18, suggesting pot use is especially dangerous for the developing brain.
"Parents should understand that their adolescents are particularly vulnerable,'" said lead researcher Madeline Meier, a postdoctoral researcher at Duke University's Center for Child and Family Policy.More than 1,000 study participants from New Zealand were tested for IQ at age 13 - likely before any significant marijuana use - and again at age 38. All were born in the town of Dunedin during a year-long span ending in 1973…"Marijuana is very dangerous drug to the brain, particularly in adolescence, and it's also a carcinogen, so it's not healthy for adults either," Dr. Harris Stratyner, vice president of Caron Treatment Centers' New York Clinical Regional Services, told HealthDay. "It's much more dangerous than we've ever given it credit for."
