A recent study published by a team of researchers from Lancaster University and The University of Lisbon indicates long-term cannabis use could result in damage to the human brain. We’re not sure how they managed to come to that conclusion however, because the study was conducted using neither cannabis nor humans.

While the study was widely reported, with news sites in several languages declaring that scientists had potentially determined the harmful side effects of habitual cannabis use, it was science news site Inverse that pointed out the problem. The researchers didn’t use cannabis.

Here’s what happened, per a Lancaster University press release: “Researchers from Lancaster and Lisbon universities studied the effects of the cannabinoid drug WIN 55,212-2 in mice and found… ” the press release then goes on to say that WIN 55,212-2 appears to demonstrate long term negative effects in the brains of mice. To paraphrase them, this stuff makes mice dumb and forgetful — and not in a funny way.

Basically, if you’re a habitual cannabis user, this is your worst nightmare. Except it isn’t, because the “cannabinoid drug WIN55,212-2” isn’t THC or CBD – the chemicals in natural cannabis that do what good weed does – it’s actually a synthetic cannabinoid designed to work on the exact same parts of the brain as THC and CBD.

Let’s talk about the differences between cannabis and synthetic weed. There are no confirmed accounts of cannabis, alone, being the cause of anyone’s death. When a news outlet reports a “Baby boy is first marijuana overdose death, doctors claim,” it’s being sensational.

This article from The Washington Post explains why there were a bunch of news outlets reporting a baby died of marijuana poisoning last year. Just like the researchers this article deals with, a doctor presented cannabis as a villain in a case where it clearly was not. Eventually the doctors who made the claims completely walked back their statements and definitively said that cannabis did not cause that child’s death.

So, again, there’s never been a confirmed death from a cannabis overdose. But, synthetic weed resulted in more than 300 people overdosing in Washington DC alone in just the past two weeks.

What is synthetic weed? We’re glad you asked. The people dying all over the world right now from smoking fake weed are, typically, overdosing on something called K2 or Spice (like all synthetic drugs it has a bunch of other names too). This is usually some potpourri that’s been sprayed with a chemical substance containing a combination of synthetic cannabinoids.

Our friend WIN 55,212-2 is among those synthetic cannabinoids. Along with others like HU-21 and AM-430, WIN 55,212-2 is found in synthetic weed products. Synthetic weed is more like bath salts than cannabis as far as the health effects are concerned.

Let’s be fair: The researchers never said they used real cannabis, and they certainly disclosed that the testing was done on mice. They even pointed out in the white paper that the trials were conducted for 30-day periods. So, while they never said they conducted “long term” research on “humans” using “cannabis,” they did say “The study has implications for both recreational users and people who use the drug to combat epilepsy, multiple sclerosis and chronic pain.” And that would lead a reasonable person to assume they mean cannabis, not K2 or Spice. Even the press release is titled “Lancaster University research shows cannabis affects memory.”

This isn’t just a misunderstanding, it’s a huge issue. Legitimate cannabis research is hard to come by. It’s not legal everywhere and it’s difficult to get funding because of the stigma surrounding its position as an illegal drug in many areas.

But, veterans with PTSD, parents with children who suffer from crippling seizures, people contemplating a cannabis cream instead of an opiate pill, or anyone else weighing the decision to try cannabis shouldn’t be tricked into using information that doesn’t pertain to them when they make important life decisions.

An observation, no matter how scientifically accurate, on how a mouse reacts to a chemical that’s not cannabis doesn’t indicate that “long-term use of either cannabis or cannabis-based drugs impairs memory” as that press release from Lancaster University begins.

The conversation on the health benefits of cannabis is muddied by this misleadingly presented research. And it isn’t fair to those who end up needlessly suffering. A cancer patient shouldn’t have to be ashamed of easing their pain with cannabis because a bunch of scientists determined that synthetic weed is dangerous to mice.

H/t: Inverse

Update 8:15 CST 7/28: an earlier version of this story incorrectly stated 300 people died in Washington DC over the past two weeks, it’s been updated to reflect 300 people overdosed.

Update 8:54 CST 7/30: Dr. Neil Dawson, one of the researchers on the study, responded to this article with the following statement:

Dr Dawson said:

WIN 55,212-2 is a synthetic cannabinoid which we know pharmacologically acts on the same receptors in the brain as THC. We have added to existing research supporting the impact of long-term cannabis use itself on the brain, such as this study in humans https://jamanetwork.com/journals/jamapsychiatry/article-abstract/2678214), and the many rodent studies supporting the disruption of cognition and memory by THC both in the short-term (https://www.sciencedirect.com/science/article/pii/S0028390804002564; https://link.springer.com/article/10.1007/BF03179772; http://jpet.aspetjournals.org/content/322/3/1067) and long-term (https://www.nature.com/articles/s41598-017-11645-8; https://www.liebertpub.com/doi/abs/10.1089/can.2017.0034). The same effects have been shown for other synthetic cannabinoids (http://journals.sagepub.com/doi/abs/10.1177/026988110401800407). Our work has extended on these publications by further confirming the memory impairment induced by long-term cannabinoid exposure and by showing that this results from disrupted interactions between the brain regions underlying this process. There are many, many more studies that support the suggestions that cannabis and cannabinoid-based drugs impair cognition and have negative effects on the brain. For those using cannabinoids therapeutically these negative side effects, which warrant further investigation, should be balanced against the positivity benefits of these drugs.

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