According to a recent survey, the cost of living crisis has caused addiction rates to rise sharply over the past eight months, with nearly a third of adults (32%) saying that they had relapsed into addiction due to the stress and anxiety causing.

In times of stress, many turn to drugs and alcohol to relieve symptoms, and a common substance that people turn to is cannabis due to its supposed ‘relaxing’ qualities. 

With this in mind, the addiction experts at the private rehabilitation centre Delamere have delved into the impact that cannabis use has on the brain as part of their toxic drug culture mapped across the UK Report. 

Martin Preston, founder and chief executive at Delamere, shared his insight on the subject: 
‘While the substance is notorious for relaxing people, the reasons behind this are undeniably worrying – even the famous munchies.’

‘It is important to note that all of this depends on the age when people first try cannabis, how often they use it, how many years they have used it, and whether tobacco is used in addition to smoking pure cannabis.’

Since 1995, Cannabis has been the most used drug in the UK, and in the year 2020, 7.8% of adults admitted to using the substance. Worryingly this figure is substantially higher than the second most used drug in the UK, powder cocaine, which stands at just 2.6%. 

However, because substance use is so prevalent across the UK, addiction experts have warned that many often overlook the dangers that using cannabis regularly can have on a person’s physical and mental health. So, what is the real effect of cannabis on the brain?

Lowered IQ

Although this would mainly occur to people that use cannabis very regularly, the risk remains prominent. A 2021 study revealed a definite link between cannabis dependency and the worsening of people’s IQs, highlighting a 1.98-point decline. 

This is because cannabis interferes with the brain’s cognitive function, allowing a person to retain new information. As a result, an individual with a cannabis dependency may suffer from short-term memory loss and forget things like appointments or need to be reminded about responsibilities. 

Changes in the brain’s reward system

The ‘reward system’ in the brain is the part that uses dopamine, a neurotransmitter, to send different messages when we feel we have been rewarded. This can be anything from a TV show that makes us feel good to our favourite foods to sex and drugs. 

When people start using cannabis recreationally, it is much easier to achieve a dopamine release than when your receptors become more hardened to the substance. This often leads to consuming more cannabis to chase the positive feeling, which can eventually slow down dopamine production altogether. 

As you are stimulating this ‘reward centre’ in your brain so often, it can, over time, become overstimulated. In the long run, this would make you more susceptible to mental illnesses such as depression and anxiety, as your brain finds it harder to produce its ‘happy chemical’. 

Loss of impulse control

It was discovered in a 2020 study that people exposed to THC (Tetrahydrocannabinol, the psychedelic aspect of cannabis) were more likely to swerve, engage in lane-weaving, and generally drive dangerously. 

This directly highlighted how much recent cannabis use impacted cognition and impulse control. Furthermore, a 2019 study by the King’s Business School and Harvard University found that ‘World Weed Day’ at 4:20pm on the 20th April every year contributed to around 20 more car accidents than usual in the UK. This suggests a link between the drug and driving recklessly. 

It could be speculated that if cannabis users are more likely to drive dangerously, they could also be more likely to engage in other kinds of risky behaviour, such as unprotected sex or violence. 

The ‘munchies’ also come into this, as THC shuts off the appetite receptors, making you feel full. As your dopamine is also spiking, cannabis will make your brain think that the food you are eating is far more delicious than it is, allowing you to gorge way past the point of being full. 

Memory loss 

There have been direct links between people smoking cannabis and their ability to remember things worsening. This is because THC has an extreme impact on the hippocampus, which is the part of the brain that deals with the processing of memories, both short and long-term. 

The loss of neurons in the hippocampus is common as people age, making it harder for them to learn new things or effectively store new memories. Being a regular cannabis user is likely to speed up this process, making it difficult to retain new information at work or college. 

A decrease in psychomotor skills

Psychomotor skills refer to the ability to join physical movements and cognitive processes. These skills involve balancing, coordinating, driving carefully, playing an instrument or using a tool. 

Alarmingly, regular cannabis use has been noted to diminish people’s ability to perform psychomotor skills, which also links back to losing impulse control.

A 2022 study highlighted that not only did cannabis impact these basic skills and affected ‘divided-attention’ tasks, which refer to distractions appearing and ‘error compensation’ tasks, where people notice an issue and correct it. 

When other people are involved, such as on the road, the consequences of cannabis use on the brain can be disastrous. 

Increased mental health problems 

Using cannabis regularly also increases the chances of developing or worsening mental health problems. Recent research has revealed that young people who use cannabis have an increased risk of developing psychosis – a condition where an individual experiences hallucinations and delusions. 

This is because the brain is still developing, which can easily be damaged by the chemicals that cannabis contains. 

Those who already suffer from a mental health condition may also find that their symptoms become worse when under the influence of cannabis – particularly in strong strains. 

In cannabis, where THC chemicals are particularly strong, it can overstimulate the amygdala in the brain, which helps regulate emotions, causing someone to experience increased feelings of anxiety or fear. 

Martin Preston concluded: ‘As Statista reported in 2020 that 29.6% of people between the ages of 26 and 59 had used cannabis at some point during their lives, it is crucial to know the risks before experimenting. Although many people feel that cannabis is harmless, it, unfortunately, comes with a host of long-term brain-related risks.’