One of the main warnings that kids hear about the dangers of pot smoking is that it will ruin their brain cells, but researchers from the University of California-San Diego along with the University of Pittsburgh, say otherwise.
In a recent study, 92 young adults and teens were examined for a total of 18 months to determine the true effects of extended alcohol and marijuana use. Each of the participants had records of using both substances in the past, and brain scans were taken before and after the testing period.
One half of the group continued to use alcohol and marijuana in their usual amounts during the study and the other participants either kept away from both substances or dramatically reduced their levels of consumption.
At the end of the study, researchers learned the participants that continued to use alcohol showed signs of brain tissue damage, while those who continued to smoke marijuana during the study didn’t show any brain tissue damage.
Joanna Jacobus, who co-authored the study, said that because of the various ways the herb is grown today, it's hard to pinpoint its effect on users.
“One reason is that marijuana can really vary, is made in different ways, and with higher or lower levels of THC and other marijuana components,” she said in an interview with the Huffington Post. “For example, one component, cannabidiol, may actually have neuroprotective effects.”
In a separate study released by the National Institutes of Health (NIH), researchers found that opinions about marijuana being harmful among teenagers is at a 20-year low, as 41.7 percent of kids in the eighth grade said periodic marijuana use is bad, compared to 66.9 percent that said dangerous results are attached to regular use.
And although previous studies have also confirmed that many commonly-used substances are actually worse for teens and adults when it comes to brain tissue damage, researchers of the NIH study still warn young people of the lasting effects of pot smoking, and say that the younger one starts, the greater chance they’ll eventually become addicted.
“Marijuana use that begins in adolescence increases the risk they will become addicted to the drug,” said Dr. Nora D. Volkow, who directs the National Institute on Drug Abuse.
“We are increasingly concerned that regular or daily use of marijuana is robbing many young people of their potential to achieve and excel in school or others aspects of life.”
In regards to the University California-San Diego study, Duncan Clark, a professor of psychiatry at the University of Pittsburgh Medical Center, says the white matter—which is the part of the brain that researchers were observing during the study—may have been damaged among the teens before the study was conducted, especially since both test groups used alcohol and marijuana regularly in the past.
“The areas of the brain that are composed mostly of connecting axons have been termed ‘white matter,’ since these areas appear white in color,” he said.
“However, prior research has not clearly demonstrated that this white matter disorganization is caused by alcohol or marijuana use. In some studies where adolescents are studied only once, white matter disorganization may have been present prior to alcohol or marijuana use.”
However Jacobson and her team did conclude that among the two substances, alcohol clearly caused more damage to the brain than marijuana did.
“We found evidence for poorer white matter tissue health in teens who engage in heavy alcohol and marijuana use compared to those who abstain,” she said.
We also found that “increasing alcohol use over 1.5 years in late adolescence was related to a decline in white matter health 18 months later, supporting a negative effect of alcohol use on the brain despite potential pre-existing differences.”