New Study Shows that Using Marijuana as a Teen is Detrimental to Brain Development

Marijuana use can negatively impact brain development, according to new research.

“Actually in childhood our brain is larger,” says Krista Lisdahl, director of the University of Wisconsin-Milwaukee brain imaging and neuropsychology “Then during the teenage years our brain is getting rid of those connections that weren’t really used and it prunes back. It actually makes the brain faster and more efficient.”

Those new connections especially involve judgment and critical thinking, so Lisdahl says that smoking or ingesting marijuana as a teenager is the worst time.

Also concerning, marijuana has become more potent since the 1970’s, as cultivators have focused on radically increasing the THC content. “The higher the THC levels, the more brain changes there are and the more there is the risk for addiction,” Lisdahl said.

A federal study recently reported that 60% of US high school seniors think that marijuana is safe, and 23% report using marijuana in the last month – more than used alcohol or cigarettes. Six percent of high school seniors report using marijuana every day, a rate that has tripled in the last decade.

“[We] see if we look at actual grades that chronic marijuana using teens do have, on average, one grade point lower than their matched peers that don’t smoke pot,” Lisdahl says.

A number of new studies, particularly one from Duke University, point out that marijuana use in teenagers can be detrimental to critical brain development. The study from Duke University focused on residents of New Zealand, from childhood through age 38, and compared IQs between marijuana users and non-users.

“We found that people who began using marijuana in their teenage years and then continued to use marijuana for many years lost about 8 IQ points from childhood to adulthood,” says study author Madeline Meier, now a professor at Arizona State University, “whereas those who never used marijuana did not lose any IQ points.”

The amount of marijuana ingested also made a difference. Those who smoked at least once daily saw a drop of 8 IQ points – and the younger the marijuana user began smoking, the greater the IQ decline. Adults who smoked marijuana as teenagers also did worse in tests of memory and decision-making, compared to adults who had not smoked pot.

However, the study pointed out that adults who used marijuana as teenagers had lower IQs to begin with.

“It’s very possible that there’s something very different to begin with among teenagers who tend to get into trouble with marijuana or who become heavy users,” said Dr. Gregory Tau, a psychiatrist and drug abuse researcher at Columbia University. “They could have subtle emotional differences, perhaps some cognitive functioning differences. It may be hard for them to ‘fit in’ with a peer group that’s more achievement oriented.”

Tau said that more funding is needed to conduct better research studies on marijuana use. “It’s not rocket science to think if you smoke weed when your brain is developing, that it can’t be ‘good’ for you, just like any ‘toxic’ substance isn’t good for you,” he says.

The Strom Law Firm Can Help with Marijuana Drug Charges

The marijuana trafficking and possession lawyers at the Strom Law Firm, LLC are dedicated to protecting the rights of our clients, providing aggressive representation grounded in our years of experience building and interpreting the laws of South Carolina. Contact us today for a free consultation to discuss the facts of your case. 803.252.4800