A provocative new book by a former New York Times links cannabis use to schizophrenia, psychosis and violence and raises questions about why this data has been ignored.
Alex Berenson, a former New York Times reporter, set out to scare people with his book about the dangers of marijuana. He makes no secret of that and he’s pretty good at doing just that.
His book, Tell Your Children: The Truth about Marijuana, Mental Illness and Violence, that was released on Jan. 8 is provocative. It may even infuriate you, as it has advocates of cannabis legalization in the United States.
It’s data heavy, drawing on scores of peer-reviewed studies and reports including the New Zealand study of cannabis users that spans nearly five decades and concluded that people who used cannabis at age 15 were more than four times as likely to develop schizophrenia. It’s information from the public and academic realms, although most of it has been ignored by mainstream media.
As one might expect from a journalist, turned-crime-novelist, turned-non-fiction-author, Berenson’s writing is spare and easy to read.
His prime assertion is that we’ve been hoodwinked by the legalization lobby. Far from being benign, cannabis — or more correctly the active ingredient THC — causes a measurable and statistically significant proportion of users to become psychotic and violent.
Is the book balanced? He admits in the introduction that it is not. However, Berenson says it is accurate, honest and truthful. Still, his conclusions are unequivocal, even though the language used by the quoted scientists and experts are more measured.
Among the evidence he cites is the 2017 report of the U.S. National Academies of Science. One of the quotes Berenson uses from it is: “Cannabis use is likely to increase the risk of developing schizophrenia and other psychoses; the higher the use, the greater the risk.”
While psychosis is more likely to develop over time, Berenson relates several criminal cases in Australia and the United States where cannabis users with no previous record of mental illness became mass murderers. How high the risk of psychosis hasn’t been definitively quantified in the United States because the incidences of schizophrenia and other several mental illnesses aren’t tracked.
But Berenson and a New York University professor crunched some numbers and concluded that the number of emergency room patients diagnosed with psychotic disorder rose 50 per cent between 2006 and 2014. The number primarily diagnosed with psychosis and secondarily with problems with cannabis tripled.
Still, a link between cannabis use and schizophrenia seems well-established. Swedish research published in the Lancet in 1987 using data from 45,570 conscripted soldiers concluded that the risk of developing schizophrenia was six times higher among heavy cannabis users. The lead author, Sven Andreasson, concluded that cannabis use was responsible for between 10 and 15 per cent of all schizophrenia cases.
A 2018 Swiss study that found almost half of people with psychosis who used cannabis became violent over a three-year period, putting their risk of violence at four times that of psychotic people who didn’t use. That study found that alcohol use didn’t increase violence among people with psychosis.
A 2013 study using data from the U.S. federal survey of more than 12,400 American high school students found that students who had recently used only cannabis were more than three times as likely to be violent as those who didn’t. Those who used only alcohol were 2.7 times as likely to be violent.
As for the cannabis industry’s claims of health benefits, Berenson is skeptical. He argues specifically against what he says has “become close to conventional wisdom since 2014” that cannabis might be a cure for opioid addiction.
Instead, he posits that North America’s much higher marijuana use than Europe’s is one reason that there is an opioid addiction crisis here.
It may be simply coincidental, but it bears noting that Vancouver is both the centre of the marijuana legalization movement and the opioid overdose epidemic. It is also where Canopy Growth, one of Canada’s largest cannabis companies, has funded a $2.5-million research project at the University of B.C. into the potential use of cannabis as a treatment for people with opioid use disorder.
Meantime, if the research and Berenson’s assertions about the links between cannabis, schizophrenia and violence are true, we may be in for a tsunami of trouble and that doesn’t even begin to address any links between marijuana and opioid addiction or even the cost of cannabis use disorder (a.k.a. addiction).
Even before Canada legalized marijuana in October 2018, its consumption rate was second only to the United States in the world. Data released last week by Statistics Canada shows that in the first eight months of 2018, 15 per cent of Canadians over 15 consumed cannabis in the previous three months with Nova Scotia at 23 per cent and B.C. at 20 per cent. (A somewhat surprising side note in the report is that two-thirds of the people who used marijuana once or twice got it free.)
In 2017, another StatsCan reported said that 1.98 million people 15 and over were using the drug at least once a week; 670,780 were daily users. The number of frequent users (at least once a week) was up by nearly 287,000 in 2012. And, there is some expectation that both consumption and frequency of use will have risen post-legalization.
And while most people are under the misapprehension that marijuana isn’t addictive, StatsCan reported in 2012 that 1.3 per cent of Canadians over all age groups had cannabis use disorder, but it was 5.1 per cent for those aged 15 to 24.
That’s the group that both the Canadian Psychiatric Association and the Canada Medical Association warned are most at risk of permanent harm from cannabis use. Yet the federal Liberal government and all of the provincial governments that set the age limits rejected their pleas to outlaw sales of cannabis to those under 21 and restrict the quantity and potency of cannabis products sold to people aged 21 to 25.
In Alberta, Ontario and Quebec, the age limit is 18, while it’s 19 in the other provinces and territories.
Throughout Tell the Children, Berenson predicts that his detractors will discredit him by drawing parallels with Reefer Madness, the 1936 film and cult hit that was so badly acted that its warnings about marijuana use were laughable. Even his title is a sly reference to the film whose original title was Tell Your Children.
Berenson is certainly correct in that prediction.
After the book’s release last week, Rolling Stone called Berenson’s theories “deeply flawed” with “dog-whistle conclusions.” Leafly (which calls itself the largest cannabis website in the world) dismissed Berenson as “a manipulative writer. His book is full of false alarms, nonsense correlations and long-debunked theories.”
Leafly didn’t provide any specifics beyond pointing to Jesse Singal’s story in New York magazine that focused on what he called “Berenson’s fishiest move.” That move was using FBI violent crime statistics starting in 2014, which had the lowest recorded number in decades. He noted that while Alaska and Oregon did legalize marijuana that year, Colorado and Washington’s legalization was two years earlier.
Singal disputed Berenson’s claim of “sharp increases in murders and aggravated assaults since 2014,” saying that while Oregon’s murder rate rose 1.0 per cent from 2015 to 2016 (compared to the national rate of 7.9 per cent), it dropped 11.6 per cent between 2016 and 2017.
But what Berenson wrote is this: “Combined, the four states saw a 35 per cent increase in murders and a 25 per cent increase in assaults between 2013 and 2017, far outpacing the national trend even adjusting for population.”
He also added a caveat. “Knowing exactly how many of these crimes are related to marijuana is impossible without researching each of them in detail.”
Maybe Berenson is making a leap. But, so too have some advocates and legislators who have touted it is a cure for almost everything.
Because if there is a single point of agreement (Berenson included), it is that we simply don’t know enough about cannabis.
Everyone agrees that with or without decriminalization or legalization, more money needs to be spent researching cannabis to determine both its risks and its benefits.
Which is why the timing of Berenson’s book and the attention it is receiving may prove awkward for Prime Minister Justin Trudeau.
His government took the biggest leap of all by making Canada only the second country in the world to legalize cannabis.
Readers and voters in the upcoming federal election need to ask whether the Liberal government took those studies into account. And if not, why not?
Because, in fulfilling the 2016 promise to legalize, it seems to have come at the expense of another one which was that a Liberal government would “ensure the federal government rebuilds its capacity to deliver on evidence-based decision making.”
Tell Your Children: The Truth about Marijuana, Mental Illness and Violence by Alex Berenson, published by Free Press.