Teens' marijuana use continues to be a serious concern for parents. And now, with the legalization of cannabis for adults in Colorado and Washington in 2012, media attention has intensified the fear factor, especially since Oregon and Alaska passed legalization measures in November.
Surprisingly, the most recent Monitoring the Future study released by the University of Michigan shows that parents have less to worry about as teenage use of marijuana has declined. Marie Veksler of Whaxy writes that until the 2014 survey, there had been a five year pattern of increase in teen cannabis use, but in the last year teens reported a 2% decrease. The lead investigator in the study, Lloyd Johnston, reported that the study showed:
"Personal disapproval of use is down some in 8th and 12th grades. Reported availability, on the other hand, is down significantly since 2013 in the two lower grades (and unchanged in 12th grade), which may help to explain the modest decline in use this year."
This could mean that the regulation component of the legalization efforts may be making a difference. The reported number of daily users of marijuana has also decreased slightly. In 2013, 6.5% of high school seniors admitted to using daily. In 2014, 5.8% of seniors said they were daily users. A decline in alcohol and cigarette use also occurred among the sample participants.
The University of Michigan conducts the Monitoring The Future survey from a sample size of 40,000 to 50,000 students in the 8th, 10th, and 12th grades from at least 40 different secondary schools throughout the United States. This is the 40th year for the study.
Medical marijuana is now legal in 23 states and recreational use is legal in four states and the District of Columbia. That means that since marijuana has heretofore been illegal, research on its health effects has been sparse, especially in regard to how pot affects developing teenage brains.
KUNC Public Radio in Northern Colorado, in a piece by Maanvi Singh, reports that pediatricians say prescribing marijuana to children is not a good idea until further research has been done, except in chronic or debilitating circumstances.
Pediatric groups have also encouraged the decriminalization of marijuana use, but are not behind the legalization movement, according to a policy paper released this week by the American Academy of Pediatrics. The reason for this is that hundreds of thousands of adolescents and teens have been arrested for possessing marijuana, the majority of whom, says Dr. Seth Ammerman, a pediatrician at Stanford University who wrote the policy paper, are minority youths. In other words, marijuana use is a public health issue rather than a criminal justice issue and should be treated in that manner.
But keeping pot away from children can be a difficult task.
"People make arguments that say, âOh, this is safer than alcohol, it's safer than tobacco, it's safer than heroin,' " Dr. Leslie Walker, chief of the adolescent medicine division at Seattle Children's Hospital says. And all that may be true, she says. "But marijuana on its own is harmful for adolescents."
The research done so far suggests that teens should not be using marijuana recreationally because of their developing brains, and because they are more easily addicted than adults. Marijuana use by anyone under the age of 21 is still illegal. The deterrents for teen usage are that alcohol and marijuana are usually too expensive for most teens to use habitually; for parents not to use marijuana in front of their kids; and controlling the extent to which companies can advertise marijuana products, especially edible products.
A new study published in the Journal of Neuroscience entitled "Daily Marijuana Use Is Not Associated with Brain Morphometric Measures in Adolescents or Adults," suggests that alcohol use, not marijuana, was responsible for previous studies finding brain changes, reports Ray Stern of the Phoenix New Times. A published abstract explains that researchers could not replicate recent research that showed that cannabis "is associated with volumetric and shape differences in subcortical structures."
Barbara Weiland of the Psychology and Neuroscience department at the University of Colorado, Boulder, and Brendan Depue of the University of Louisville in Kentucky compared MRI scan reports of 29 adult and 50 adolescent daily marijuana users with the same number of non-users. The team found a lack of differences between the two groups' brain activity that was unexpected.
Dr. Frances Jensen, professor and chair of the Department of Neurology at the University of Pennsylvania Perelman School of Medicine, explains that she wrote The Teenage Brain to explain and explore how the brain grows. Particularly, Dr. Jensen wanted to delve into why teenagers can be so impulsive, moody, and have poor decision-making faculties.
"We have a natural insulation â¦ called myelin," she says. "It's a fat, and it takes time. Cells have to build myelin, and they grow it around the outside of these tracks, and that takes years."
WMRA-NPR reports that Jensen says brains are not fully mature until the early 20s, and sometimes later than that. This research also highlights why teens can be so susceptible to addictions, like alcohol, drugs, smoking, and digital devices, and why they can become addicted so rapidly. Unfortunately, the effects on adolescent brains are also more permanent. For example, it can become more difficult to "lay down new memories" when a teen has become addicted to cannabis. Not only that, but in the short term, teenagers who binge drink on the weekends, could suffer effects on into Thursday or Friday of the school week.