No brainer: Smoke weed every day and you’ll flunk school, report says

Teenagers under 17 who use cannabis daily are 60 per cent less likely to complete high school or get a degree than peers who have never taken the drug, researchers say. They are also nearly seven times likelier to attempt suicide and are almost eight times likelier to use other illicit drugs later in life. The data, published in the journal The Lancet Psychiatry, comes from an analysis of three large, long-running studies in Australia and New Zealand. The studies considered the welfare of several thousand young people, who were assessed regularly between the ages of 13 and 30.

Our findings are particularly timely, given that several U.S. states and countries in Latin America have made moves to decriminalize or legalize cannabis, raising the possibility that the drug might become more accessible to young people.

Richard Mattick, a professor at the National Drug and Alcohol Research Centre in New South Wales

As much as possible, the review took into account factors such as gender and socioeconomic status that could skew the picture. The researchers conceded it was possible that some cannabis users turned to the drug after dropping out of school, rather than before. But the figures clearly showed that the more cannabis was consumed, the likelier it was that a teen would not finish secondary education. Other experts said the results of the study were not surprising but still provided needed data to support anecdotal evidence about pot use.

None of the findings will surprise mental health workers, and indeed previous studies have reported similar findings for each of the outcomes separately.

Robin Murray, a professor at King’s College London, Institute of Psychiatry, Psychology & Neuroscience

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