Using Marijuana Before The Age Of 18 Leads To Lower IQ Later In Life?
Joe | Aug 27, 2012 | Comments 1
If So, Another Reason to Legalize
According to a new study out of New Zealand, those who “become dependent” on marijuana before the age of 18 show lower IQ scores later in life.
The researchers didn’t find the same IQ dip for people who became frequent users of pot after 18. Although experts said the new findings are not definitive, they do fit in with earlier signs that the drug is especially harmful to the developing brain.
And while no one is advocating marijuana use before the age of 18, it is important to keep this study in perspective, especially considering who funded it.
“I think this is the cleanest study I’ve ever read” that looks for long-term harm from marijuana use, said Dr. Nora Volkow, director of the National Institute on Drug Abuse, which helped fund the research.
Ken Winters, a psychiatry professor at the University of Minnesota and senior scientist at the Treatment Research Institute in Philadelphia, said the new findings aren’t definitive, but they underscore the importance of studying how marijuana may harm young people. He had no role in the work.
Also interesting is the location of all the study participants, from one town in New Zealand; environment always has a part to play in continued intelligence.
The study drew on survey data from more than 1,000 people in New Zealand, everybody born in the town of Dunedin during a year-long span ending in 1973. In addition to IQ tests, they were interviewed five times between ages 18 and 38, including questions related to their marijuana use.
At age 18, 52 participants indicated they had become dependent on marijuana, meaning that they continued to use it despite its causing significant health, social or legal problems. Ninety-two others reported dependence starting at a later age.
Researchers compared their IQ scores at age 13 to the score at age 38 and found a drop only in those who had become dependent by 18.
Those deemed dependent in three or more surveys had a drop averaging 8 points. For a person of average intelligence, an 8-point drop would mean ranking higher than only 29 percent of the population rather than 50 percent, the researchers said.
The truth is many things contribute to IQ, including the motives of those asking the questions. No doubt this study will be used by those against legalization as a feather in their cap, but it shouldn’t be. Even if this study is dead on accurate about teen marijuana use, legalization is the only way to control the market and limit teen use as much as possible.
As the old saying goes, “drug dealers don’t check I.D.”