You’ve probably heard it from your parents or from anti-drug campaigns, but let’s put this question to rest: does cannabis lower IQ?


For as long as cannabis has been a topic of conversation, there have been arguments for why it is harmful to users. One basis for these arguments is the idea that cannabis can lower IQ over time. Many studies have materialized over the years demonstrating the disparaging effect cannabis has on its users’ cognitive abilities. But is it all actually true?


Today, Chronic Haze seeks an answer to this long-asked question. We’ll examine arguments both for and against, and come to a conclusion of our own. Ready? Let’s get into it.


Arguments For Cannabis Lowering IQ



The claim that cannabis lowers IQ has been supported by numerous studies, especially in cases where users begin early, such as in adolescence. Some notable ones include a study from New Zealand, in which researchers closely studied 1000 people to observe the effects of cannabis on brain function. The participants were born in the 1970s, and the study followed them from age 3 all the way up to age 45, with cannabis use and IQ being assessed at certain age intervals.


The study claimed that those who started using cannabis in adolescence and consumed it frequently (at least weekly) over a long period of time were likelier to develop cognitive issues. These included issues with problem-solving and information processing, difficulty with subjective thinking, and an average IQ drop of 5.5 points. Close friends of these individuals described them as having attention and memory problems, and this decline tended to become apparent around age 38.


Another study conducted by researchers at the Royal College of Surgeons in Ireland corroborated past assertions that cannabis use in adolescents was linked to mental health diagnoses such as schizophrenia. They also claimed that cannabis use led to a 2-point IQ decrease over time, and that these individuals had worse education and employment outcomes.


As you can see, arguments supporting the idea that cannabis lowers IQ are definitely not in short supply. But what about the counterarguments?


Arguments Against Cannabis Lowering IQ



An interesting study regarding cannabis use and IQ has been garnering discussion as of late, and it challenges the assertion that cannabis use directly lowers IQ.


In the study, researchers from California and Minnesota collected data on sets of adolescent twins, one of which became a cannabis user while the other did not. They were assessed at a young age, prior to adolescence, and then again in late adolescence. Similarly to the New Zealand study, many cannabis-using twins showed a decrease in IQ, and the mean score of the cannabis-using group was lower overall. However, this study had some key differences in its results.


Firstly, in many cases where a cannabis-using twin exhibited an IQ decrease, their non-cannabis-using counterpart did as well. Additionally, when controlling for the use of other substances, such as tobacco and alcohol, these drops in IQ were found to be statistically insignificant and uncorrelated to cannabis use.


So what’s going on here? Simply put, there are other factors at play. The researchers’ findings indicated that, when factoring in the effects of nicotine, binge drinking, and other forms of substance abuse, the effects of cannabis on cognitive decline were relatively unsubstantial. The researchers also took socioeconomic factors into consideration, as some individuals who exhibited drops in IQ came from families that did not value education. Behavioural traits such as impulsivity, risk-taking, and delinquency were also instrumental in predicting cases of lowered IQ.


The results of this study caused a ripple effect, with other researchers corroborating the argument that cannabis and cognitive decline are not necessarily causally linked. These include the researchers from the New Zealand study, who themselves conducted another study on twins that served to debunk the association between cannabis use and lower IQ.





So what’s the takeaway here? To put it plainly, there isn’t a definitive answer yet, and more research needs to be done. However, using a more nuanced approach, we can deduce that cannabis use is not necessarily tied to cognitive decline. While there are certainly cases in which cannabis users experience a decrease in IQ over time, there are other factors that can certainly play a role in this phenomenon.


It’s important to have an accurate picture of the things we consume, whether it’s the food we eat or the substances we use. While it’s certainly understandable to want to dodge anything that would negatively impact your brain, it’s not necessarily better to live in fear of something based on misconceptions. For those that enjoy it, cannabis can have immensely positive impacts on mental well-being, and it would be unfortunate for people to preclude themselves from the benefits of cannabis due to faulty or incomplete information.


One thing’s for certain, though: if you’re a minor, you shouldn’t be consuming cannabis. As can be gathered from the aforementioned studies, using cannabis while your brain is still developing puts you at risk of very real cognitive issues. Childhood and adolescence are pivotal times in one’s development, and the body’s naturally-occurring cannabinoids are what’s best for your system right now. 


Wanna Learn More?


Whether you just need a break or are curious about experiencing something new, you’ll find what you’re looking for at the Chronic Haze online store! We’ve got tons of amazing cannabis products, with same-day delivery and curbside pickup for your convenience.


Not within our main delivery zones? We offer nationwide delivery all across Canada! If you’re looking to buy cannabis online, make an account with us and check out our selection today! Don’t forget about our Happy Hour timeslots on Mondays and Tuesdays! Visit our Deals section for more info!


Also, did you know that cannabis may have an effect on the production of testosterone? Check out this blog post to learn more!

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