Should teenagers smoke weed?

The short answer is no..., not until their brain is fully developed which is usually about when they reach 25 years old. Below I will give the reasons why based on my own life experience.

This is a warning from history as they say. Did you start smoking cannabis in your early teens? Still, smoking it? Well, I have some news for will stunt your growth. Not your height, although if you are mixing your weed with tobacco it actually could. I am talking about your emotional growth.

You see in my misspent youth I hung around a lot of Stoners. Lovely guys who loved their music and Hash as we used to call it back then in the early eighties. For some of us, it was just at the weekends because during the week we had to go to school :)

We smoked Red Lebanese or Pakistani black resin, which is now called Soap Bar. It was lovely, mellow stuff with an active THC content of around 3%.THC is the active ingredient that gets you stoned. To put that figure into some kind of perspective, Weed nowadays has an active THC content of 20%, with strong strains of up to 30%! It's essentially a different drug; but that's for another blog post...

This post is about my observations of two of my closest friends who started smoking Cannabis around about the age of twelve and carried on smoking daily until the present day. Now they started off smoking Cannabis resin which had an active THC content of only 4%, not the 20% Weed that is freely available today.

On a daily consumption of 4% Hash, very quickly I noticed changes in their behaviour and their lifestyle. The first noticeable thing was their lethargy to work and ambition. In fact, both of them have not had a job since the 1980s.Instead, they prefer to stay in their apartments,living on Benefits,smoking weed...period.

Even in the first few years, they became quite obsessive about their routine, especially when it came to Weed. They could spend easily a whole hour telling you in forensic detail about the Weed they had. How it smelt, felt, tasted and every minute detail about the high. Now once in a while, that's fine, but every time I would spend time with them they would launch into a rant about the latest batch they had bought.From there,I noticed their appearance became more and more unkept and their apartments more and more untidy.

Then the mood swings started, sometimes out of nowhere they would start being overly sensitive to some remark that was said and storm off without any explanation or farewell. This was just the start and from there they both became more and more socially isolated and actually quite bitter and resentful about my and our other friends' success and ambition, to the point that they were no fun at all to be around. It was like they were stuck in time...

It turned out they were stuck in time, psychologically. Fast forward forty years and sadly one of them is dead. I will discuss the reasons later in this blog. The only other dramatic change was the strength of the cannabis, everything else in the other one that was still alive had remained the same. He still lives in the same apartment, listening to the same music, on vinyl I may add, eating the same food he ate as a teenager, Mars bars and fast food and still complaining about exactly the same things he was complaining about in the 1980s!

I would get so frustrated at him and just wanted to shout at him "grow up!" and that was it...he hadn't developed mentally or emotionally at all. I decided to investigate this further and what I discovered about smoking Cannabis in your early teens, first of all, shocked me but also confirmed what I was witnessing in my friend's life.

Some of the best research is coming from Sweden, specifically Thomas Lundquist and Dan Ericcson of the Addiction Treatment Centre, University Hospital in Lund.

The first thing I learned was that if you start smoking weed in your teens, you basically freeze-frame your emotional growth. For example, if you started smoking at the age of 14, you will keep acting and thinking like a 14-year-old into your adulthood if you smoke cannabis daily and excessively. Your speech and vocabulary will be appropriate for the age you started smoking even though you are a fully grown adult physically!

But that's just the start. You will experience feelings of being misunderstood and lonely. You will find it hard to find the exact words to express yourself. The ability to think or engage in concrete or even abstract thinking weakens considerably. You see our brains' don't fully develop until we reach our early 20's; so if you engage in daily, heavy cannabis use it will dramatically impair the brain's growth and cognitive function.

Please keep in mind that those findings are based on a THC level of 6-8%, not the 20-30% levels of THC which is present in weed nowadays! But as I say this is just the tip of the iceberg. In my next post, I will discuss in more depth the consequences of smoking cannabis in your teens.

Andy MacArthur is a Clinical Hypnotherapist based in Edinburgh, Scotland who specilaises in treating anxiety and addiction to Cocaine and Alcohol.If you need help reach out to him at and you can arrange a free telephone consultation.


© 2020 by Andy MacArthur, Clinical Therapist.