Study links teenage cannabis use to depression

Study links teenage cannabis use to depression

DEPRESSION LINK: Scientists believe they have found evidence of a connection between teenage use of cannabis and the development of depression

CANNABIS USE by teenagers has been linked to depression in young adults by authors of a new study.

The researchers say they have found evidence that supports a link between use of the drug by teenagers and the onset of depression in adulthood.

Scientists at the University of Oxford and McGill University in Montreal, who collaborated on the research, described the use of cannabis by young people as an “important public health issue”.

They recommend that pre-teens and teenagers should avoid using the drug concluding that is associated with a significant increased risk of developing depression or having suicidal thoughts or attempting suicide.

Among adolescents around the world, cannabis is the drug used most commonly. Roughly one in nine young people consume the drug each year in England and Wales.

Other studies have investigated the link between the use of cannabis and the development of psychosis but scientists have not spent as much time looking into the link between its consumption and the effects on mood and suicidal behaviour in young adults.

“This is important information for parents and teenagers. The risk is modest, but it can have a devastating impact,” the BBC reported professor Andrea Cipriani, one of the study’s co-authors, said.

The team of researchers looked at 11 studies comprising more than 23,000 young people in order to reach their conclusions.

Those who used cannabis before 18 increased their risk of developing depression in young adulthood (before the age of 35) by 37 per cent, the study found.

The scientists believe that around 7 per cent of cases of depression in young adults could be prevented if individuals avoided using cannabis as teenagers.

Based on the cases which the study looked at, the figure would be the equivalent to avoiding 60,000 cases of depression in the UK, 25,000 in Canada and over 400,000 in the US.

Despite the study’s findings, the research does not definitively prove that cannabis was the cause of depression in later years.

However, the scientists have called on parents to be less relaxed about their teenage children using the drug.

“Although individual-level risk remains moderate to low and results from this study should be confirmed in future adequately powered prospective studies, the high prevalence of adolescents consuming cannabis generates a large number of young people who could develop depression and suicidality attributable to cannabis. This is an important public health problem and concern, which should be properly addressed by health care policy,” the authors of the study concluded.

For helplines, readers in the UK can contact Samaritans by calling 116 123 (free from any phone) or email A wider list of services can be found via mental health charity Mind here.

Readers in the US can call the National Suicide Prevention Lifeline on 1-800-273-8255.

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