Cannabis: Is it good or bad for you? Health benefits and drawbacks explained

Teenagers and young adults should avoid trying cannabis, academics have said following a major new review.

New research published in the British Medical Journal (BMJ) found that while cannabis compounds could be helpful for people with certain medical conditions, taking the drug could be detrimental for certain groups of people.

Researchers behind the study said that while marijuana does have some medicinal benefits, its use is also linked to a decline in mental health and cognition.

The authors said that cannabis should be avoided among young people while their brains were still developing, arguing that most mental illnesses were first identified during teenage years and young adulthood. This was also a period when “cognition is paramount for optimising academic performance and learning”.

Here are some of the risks of cannabis, both found in this study and others.

Worse car driving

The study bin the BMJ found that taking cannabis increases the risk of car crashes among drivers, due to the cognitive problems it creates.

Pregnancy concerns

Researchers also discovered a connection between poor outcomes for babies and pregnant women taking the drug.

Damage to mental health

Authors of the BMJ-published study said: "Convincing or converging evidence recommends avoiding cannabis during adolescence and early adulthood in people prone to have or have mental health disorder"

Respiratory problems

Smoking cannabis can lead to respiratory problems similar to those associated with tobacco smoking, including chronic bronchitis and lung irritation.

Addiction potential

While the addiction potential of cannabis is generally lower compared to substances like opioids, some individuals can develop a dependence on it, leading to withdrawal symptoms when users try to give it up.

Legal consequences

In many places, including the United Kingdom, cannabis is illegal to possess or keep for recreational use, and can be the subject of criminal convictions.

But medicinal cannabis – or cannabis-based medicines – can be used. Specialist doctors can prescribe medicinal cannabis for conditions such as severe epilepsy, cancer patients suffering side effects from certain drugs and patients with multiple sclerosis.

Researchers found upsides of cannabis largely revolved around the benefits of cannabis-based medicines.

Cannabis-based medicines were also found to “improve quality of life” among patients with inflammatory bowel disease and were found to be effective in palliative care.

Cannabidiol was considered to be beneficial for people with epilepsy to help them avoid seizures - and cannabis-based medicines could also help reduce chronic pain and could help reduce spasms among people with multiple sclerosis.

It could also help reduce nausea and vomiting among patients with a range of conditions and help improve the sleep of cancer patients.