Tuesday, January 15, 2019

How Safe Is Weed?

When it comes to marijuana, we don’t know. We don’t seem to have any reliable scientific research about the effects of weed. As the nation dives headfirst into legalization of marijuana, we should know more. We don’t. All we know is that Justin Trudeau's Canada is leading the march toward legalization... and that should cause us to have some serious doubts.

Writing in The New Yorker Malcolm Gladwell aims to be judicious in his appraisal of the research. In many ways it raises as many questions as it asks. (Via Maggie’s Farm).

Gladwell sums up the results of recent research:

A few years ago, the National Academy of Medicine convened a panel of sixteen leading medical experts to analyze the scientific literature on cannabis. The report they prepared, which came out in January of 2017, runs to four hundred and sixty-eight pages. It contains no bombshells or surprises, which perhaps explains why it went largely unnoticed. It simply stated, over and over again, that a drug North Americans have become enthusiastic about remains a mystery.

And yet… a recent peer-reviewed study, published in the Journal of Neuroscience, suggests that adolescents, people whose brains have not developed fully, incur a risk when they smoke weed. Even in seemingly small quantities weed can change the structure of the adolescent brain. Of course, as Gladwell notes, these studies do not often factor in the different kinds of weed and the different concentrations of certain chemical compounds. It's devilishly difficult to do a scientific study when the substances being tested are anything but identical.

The Daily Mail has the story:

Just one or two joints is enough to change the structure of a teenager's brain, scientists have warned.

And the drug could cause changes affecting how likely they are to suffer from anxiety or panic, according to a study.

Researchers found 14-year-old girls and boys exposed to THC – the psychoactive chemical in cannabis – had a greater volume of grey matter in their brains.    

This means the tissue in certain areas is thicker, and it was found to be in the same areas as the receptors which marijuana affects.

Experts said thickening of brain tissue is the opposite of what usually happens during puberty, when teenagers' brain matter gets thinner and more refined.

And also:

Researchers from the University of Vermont scanned the brains of teenagers from England, Ireland, France and Germany to study marijuana's effects. 

They found differences in the volume of grey matter in the amygdala and the hippocampus.

These sections are involved with emotions, fear, memory development and spatial skills – changes to them suggests smoking cannabis could affect these faculties. 
Scientists said theirs is the first evidence to suggest structural brain changes and cognitive effects of just one or two uses of cannabis in young teenagers.

And it suggests as teenagers brains are still developing, they may be particularly vulnerable to the effects of THC.

In today’s cultural climate we all seem to recognize that something is wrong with the adolescent brain. We tend, as a rule, to blame it on social media and hand-held gadgets. And yet, if a third of 10th graders have tried weed, we should also pay some attention to its influence on the developing brain. And we ought perhaps to be more judicious  before pronouncing it perfectly safe. And before encouraging its use:

Dr Orr concluded: 'Almost 35 per cent of American 10th graders have reported using cannabis and existing research suggests that initiation of cannabis use in adolescence is associated with long-term neurocognitive effects.

'We understand very little about the earliest effects of cannabis use, however, as most research is conducted in adults with a heavy pattern of lifetime use.

'This study presents evidence suggesting structural brain and cognitive effects of just one or two instances of cannabis use in adolescence.'  


trigger warning said...

The Manichean-style arguments about marijuana safety, and indeed the safety of any substance in the environment from cigarette smoke to vitamin C, suffer from one vital omission: specification of the dose - response curve. Consider thallium. Thallium is an extremely toxic metal. It has been used in assassinations. Even so, radioactive (!) thallium-201 is deliberately injected into patients by medical professionals to run cardiological stress tests. As toxicologists are wont to say, the poison is in the dose.

I have no doubt that chronic marijuana smoking is dangerous, for the tars present in the smoke if for no other reason. This would be particularly true for juvenile organisms of any species. Compounding (no pun intended) the problem is the existence of very powerful, genetically engineered, variations of marijuana. Since a toxic dosage level is unknown, the dosage present in any given sample purchased retail is unspecified, and the dosage is somewhat dependent on the delivery method, it's best to simply avoid it.

Ares Olympus said...

Gladwell's opener says well "Permitting pot is one thing; promoting its use is another."

What is most confusing to me is why anyone would willing take an illegal drug from an unknown origin, almost I guess this is more likely and dangerous with heroin. But was legal, at least someone could be held to account if it has been laced.

Legalizing for adults shouldn't clearly make it easier to get by teens but if it is cheaper, probably it will increase usage. There has to be some optimal balance between reefer madness fear mongering that is laughed at and just the facts that mostly says "we don't know" in so many important questions.

Are mental ill people more drawn to drugs, or do drug actually cause some mental illness? I'd argue that mental illness is party about becoming detached from reality, not like the paranoia you experience from lack of sleep, and drugs that distort our perceptions make it easier to slide into that detachment, and it makes more likely your life will be a mess, and once you have an instant escape painful awareness, why ever stop?