Marijuana Pixabay
Image source: Pixabay.

For all intents and purposes marijuana legalization has been a practically unstoppable force for the better part of two decades.

Marijuana's tug of war with Congress
Although we've witnessed a couple of rare defeats -- such as Florida's failed medical marijuana amendment in 2014, which missed out on a passing vote by just 2%, and Ohio's Issue 3, which was steamrolled in last month's elections -- marijuana's influence and the public's perception of the drug have grown at a remarkable pace.

Roughly 20 years ago there wasn't a single state that allowed physicians to prescribe marijuana, nor was there a legal shop for consumers to obtain marijuana for medicinal use. Today, consumers in 23 states can obtain medical marijuana prescriptions (the qualifying diseases vary from state to state), and in four states -- Oregon, Washington, Colorado, and Alaska -- recreational marijuana has been legalized.

How is this possible? It's primarily a function of consumers softening their stance on marijuana. Two decades ago only around one-quarter of respondents in national surveys had a favorable view of marijuana. Today, national polls regularly show that a slight majority of respondents have a favorable view of the drug. When speaking of marijuana strictly in terms of medicinal use, consumer favorability rises even higher. On the surface, it would appear that America would like to see decades-old marijuana laws reformed at the federal level.

Congress has other ideas. Lawmakers on Capitol Hill want to see substantial data on marijuana's effects on the body and mind before they'll consider altering their stance on the drug. For the time being Capitol Hill has taken a hands-off approach to managing marijuana at the state level, but formulating a safety profile for marijuana certainly isn't going to happen quickly.

Forging a safety profile for marijuana is like putting together a 50,000 piece puzzle, and last week a new -- and alarming -- puzzle piece was added to the equation.

Ndarc Fb
Image source: National Drug and Alcohol Research Centre.

This concerning study raises an important point
According to a report from researchers out of King's College London and Sapienza University of Rome, there may be potential safety concerns with so-called "skunk" marijuana.

Researchers have postulated that the differences in THC content between the marijuana people are using today and the marijuana prior generations have used could be leading to a number of unknown psychological side effects. The report from King's College and Sapienza University of Rome demonstrated, albeit in a small patient pool, that "skunk strains," or modern marijuana strains with higher concentrations of THC, the psychoactive component of marijuana, led to smaller amounts of white brain matter inside the corpus callosum.

The corpus callosum is the neural pathway that joins the left and right hemispheres of the brain and is responsible for the "communication" of the two halves. It's also believed to be rich with cannabinoid receptors, leading to a greater potential effect from marijuana use.

In its study, researchers at the South London and Maudsley NHS Foundation Trust performed an MRI on 56 patients who had first experienced an episode of psychosis, then compared this with 43 healthy participants from the surrounding community. The findings showed that corpus callosum matter was consistently lower in users versus non-users, and it also demonstrated that the use of skunk marijuana had a larger, and more adverse, impact on the corpus callosum.

Dr. Tiago Reis Marques, a senior research fellow at King's College London, had this to say:

"This white matter damage was significantly greater among heavy users of high potency cannabis than in occasional or low potency users, and was also independent of the presence of psychotic disorder."

Researchers concluded that medical professionals, lawmakers, and the public need to be better educated about what impact differing strain strength may have on a person's mental and physical state.

Finer points to keep in mind
On one hand, readers would be urged to keep in mind that we're talking about a very small patient pool here -- less than 100 patients. It would be foolhardy to assume that MRI scans of less than 100 people would be representative of the global population. Additional studies encompassing a greater number of patients are needed.

Laboratory Pixabay

Image source: Pixabay.

On the other hand, this isn't the first time we've witnessed a link between marijuana containing higher levels of THC and psychosis. In February, according to online news source UPI.com, researchers in the U.K. discovered that approximately 24% of 410 patients who were treated for a previously undiagnosed psychotic disorder were smoking high-potency marijuana on a daily basis. Again, this doesn't establish a direct link between high-potency marijuana and adverse mental effects -- just because patients used marijuana doesn't mean it caused their mental disorder -- but it does add more fuel to the fire that there could be a connection and that more research is needed.

More questions raised means an even longer wait for supporters
What can this latest marijuana study teach us? Basically, that we still don't have all the answers. You'll have no shortage of longtime users who disagree with that assessment, but ultimately what matters is what Congress thinks of marijuana -- and at the moment they have no plans to change their assessment.

Marijuana Pixabay

Image source: Pixabay.

What would it take for Congress to completely alter its perception of marijuana? In addition to a favorable benefits-versus-risk profile, Congress would need to see clearly defined plans on a state and/or federal level of how the drug would be kept under some form of regulation, as well as how it would be economically beneficial to support its legalization. The ongoing legalization effort in select states could go a long way to supporting these back-end concerns, but not much can be done to speed up the clinical study process.

For marijuana supporters and investors it means the wait for legalization is probably going to continue for many years to come (if it comes at all). There's little denying that there's huge market potential behind marijuana's proposed legalization at the federal level, but it's possible that the restrictive federal tax system, minimal access to banking services, and hyper-competitive black market could keep marijuana-based businesses from succeeding or even surviving over the long run. This all adds up as a big red flag for investors.

Sean Williams has no material interest in any companies mentioned in this article. You can follow him on CAPS under the screen name TMFUltraLong, track every pick he makes under the screen name TrackUltraLong, and check him out on Twitter, where he goes by the handle @TMFUltraLong.

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