While any substance use by teens is not a good idea, new studies show that it isn’t cannabis use that is giving teens lower IQs. Despite all the stereotypes of lazy and stupid, vacant-eyed ‘stoners’, it turns out that the biggest factors in lower IQ are tobacco and alcohol.
Big study reveals truth
Recently published in the Journal of Psychopharmacology, and conducted by the Avon Longitudinal Study of Parents and Children Cohort (ALSPAC), the study found that cannabis use in teens has no significant detrimental effect on IQ when compared with similar teens who had never reported trying it. With a huge pool of over 2,200 subjects, tested at 8 years old and again at 15, it is one of the largest and most accurate studies to date.
A previous study, conducted by PNAS and released in 2012 claimed that persistent cannabis use in teens had a negative effect on IQ compared to teens who did not use, especially when started young.
Tobacco use causes lower IQ’s
Controlling the variables of cigarette and alcohol use, mental health symptoms, behavioral problems, and socio-economic factors in results, the ALSPAC study reveals that adolescents, even those who had used cannabis more than 50 times during the period, did not differ in IQ test performance over controls. Of the 2,200 children in the study, 24% reported having tried cannabis at least once by age 15.
More detailed analysis of the results when factoring out cannabis users showed a strong diminishing effect on performance in those who used tobacco and alcohol when the same controls for other variables were applied.
Difficult readings due to overlap
The one area that many studies have difficulty in separating is the one in which often cannabis use is preceded and accompanied by tobacco use. 90% of cannabis users in the study also used tobacco, or mixed it into their cannabis (often to avoid detection). To be even more accurate, further studies must find test subjects that over the course of time choose not to partake in tobacco and cannabis together, rather sticking with one or the other. Since these studies obviously do not want to encourage any use of substances, it is a matter of having a large enough pool of participants with a diverse enough life experience to give a large pool of each category.
Tobacco is a pervasive worry with young adults, compared to cannabis as it is both cheap, and not securely monitored. Often access to tobacco is as easy as reaching into a coat or pulling a few cigarettes from the parent’s pack of cigarettes on the counter. It is also much easier for teens to get tobacco from older classmates who will buy it for them. Seen as a common cultural vice, it is accepted across the world and frustratingly considered safe for short-term use.
This post was originally published at this location