A False Link Between Marijuana and Mental Illness

The article published today in “Health News” makes the claim that smoking marijuana is “linked” to early onset of mental illness.

However, although the article implies some sort of cause and effect, that conclusion has no scientific basis. In fact, the authors of the study don’t even bother investigating whether marijuana use causes mental illness or if people with mental illness have a higher rate of smoking marijuana than the general public.

If marijuana caused mental illness, then cultures that have a higher rate of marijuana smoking than the U.S. should have a higher rate of mental illness. But in fact, the opposite is true. Cultures with higher rates of marijuana consumption have lower rates of mental illness than the United States. This would indicate that rather than marijuana causing mental illness, as your article implies, it is people with mental illness who are self medicating with marijuana in order to alleviate their symptoms.

This (more correct) reading of the data, however, does not fit the narrative being presented by the politicians who are making their careers by “getting tough” on marijuana smokers, nor does it fit the narrative of the manufacturers of the currently legal psychotropic drugs, like Prozac and Zoloft, who stand to lose billions of dollars if medical marijuana is legalized, and who funnel millions of dollars to those politicians who present their dubious science as fact.

Had your newspaper even taken the time to Google the Archive of General Psychiatry, you would have found that the “study” you cited was conducted by the “Genetic Risk and Outcome in Psychosis (GROUP) Investigators,” who publish only articles against medical marijuana. That alone should raise a red flag to anyone with a basic understanding of scientific research. When someone conducts numerous studies and publishes many articles that all draw the same conclusion, whether the evidence leads to that conclusion or not, the critical eye should suspect some ulterior motive at work. It’s not possible to keep an open mind when you have an axe to grind.

William Smith, Baltimore

– Letter from The Baltimore Sun.

Psychosis Triggered by Smoking Pot? Marijuana Study Says Yes

by CBS News

(CBS) Advocates of medical marijuana say pot has all sorts of health benefits. Maybe so, but a new study from Australia suggests that smoking pot can drive some people crazy – or at least make them go crazy sooner than they would have if they had never picked up the pipe.

The study, published online in “Archives of General Psychiatry,” shows that potheads develop severe mental illnesses like schizophrenia about 2.7 years earlier than people who don’t use marijuana.

The link between smoking pot and mental illness appears strongest in children 12 to 15 years of age, Reuters reported. They develop mental illnesses that might not have shown up until their late teens or twenties – if they showed up at all.

“The results of this study provide strong evidence that reducing cannabis use could delay or even prevent some cases of psychosis,” study author Dr. Matthew Large, of the University of New South Wales, said in a written statement.

What explains the link between marijuana use and severe mental illness? One possibility, according to Dr. Large, is that pot smoking actually causes psychosis. Other possibilities, he said, are that pot might hasten the onset of psychotic symptoms in vulnerable people – or make symptoms of psychosis worse.

But other scientists say there are alternative explanations.

Michael Rice, a psychiatric nurse practitioner at the University of Nebraska Medical Center in Omaha, told HealthDay that people who are predisposed to schizophrenia might gravitate to smoking pot because it has a beneficial anti-inflammatory effect.

Whatever the explanation, Dr. Large and his colleagues are eager to publicize the risks pot smoking poses to young children, writing “Even if the onset of psychosis were inevitable (for a particular individual), an extra two or three years of psychosis-free functioning could allow many patients to achieve the important developmental milestones,” MSNBC reported.

“I’m not a marketing expert,” Large said, “but we have to find a way to tell young kids to hold off.”


– Article from CBS News.