Could This New Marijuana Study Smoke Pessimists?

By Sean

Source: Flickr user Poporin.

To put it mildly, marijuana is a complicated issue.

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Over the past decade we've seen public opinion on the drug make a complete 180, moving from a majority of people preferring it remain illegal, to a majority of the public now favoring its legalization in some form (either medically or recreationally).

Marijuana's dual allure The rationale behind marijuana legalization takes two main forms. From the perspective of individual states, it offers a fresh way of generating tax revenue without having to boost taxes on all residents within a state. Both recreational and medical marijuana being prescribed/sold bear taxes that consumers pay. These taxes can help states bridge budget deficits without affecting all residents' pocketbooks.

Source: GW Pharmaceuticals.

Secondly, some consumers and physicians want to see marijuana approved for medical purposes following a number of studies that have highlighted its possible benefits. As we looked at last week, marijuana, or, more specifically, extracts from the cannabis plant known as cannabinoids, have been shown to be effective in early studies as a treatment for type 2 diabetes, schizophrenia, and perhaps even aggressive forms of brain cancer.

But, there's also one glaring reason marijuana has been and will likely continue to be held back: The federal government classifies it as a schedule 1, or illicit, drug. With few longer-term studies undertaken to highlight the potential benefits of marijuana, most of the data the federal government has to dig through highlights marijuana's risks.

However, a fresh study released two weeks ago by the University of Colorado at Boulder could have opponents of marijuana changing their tune.

Great news for marijuana proponents According to neuroscientists at the University of Colorado at Boulder, and as published in the Journal of Neuroscience, marijuana use does not lead to volume or shape changes of the brain.

In previous studies that had examined whether marijuana had played a role in causing volumetric or shape differences in users' brains, few controls were allotted for those who also consumed alcohol. In the six-author study published two weeks ago, researchers matched marijuana users versus non-users with a focus on external variables such as alcohol (i.e., pitting marijuana users versus non-users who drank similar amounts of alcohol) to reduce or eliminate the effects these variables could have on the study's final results.

Source: Flickr user Carlos Gracia.

Utilizing high-resolution MRI scans, researchers examined 29 adult marijuana users, 29 adult marijuana non-users, 50 adolescent users, and 50 adolescent non-users, and found little difference between the brain scans of the two groups.

In the words of the researchers, "We acquired high-resolution MRI scans, and investigated group differences in gray matter using voxel-based morphometry, surface-based morphometry, and shape analysis in structures suggested to be associated with marijuana use, as follows: the nucleus accumbens, amygdala, hippocampus, and cerebellum. No statistically significant differences were found between daily users and nonusers on volume or shape in the regions of interest."

In plainer English, the findings would appear to suggest that marijuana use doesn't have a negative effect on the shape or volume of the brain in areas that control decision-making and memory.

Why this is importantThis study could be just the kick-start that marijuana proponents need to gain funding for additional studies that take a closer look at whether or not marijuana has positive effects against certain diseases and ailments.

Even more so, studies like this could pave the way for marijuana to be tested by pharmaceutical companies in a broader swath of the population.

Among disease indications that have shown significant promise to be treated by cannabinoids is epilepsy. Unfortunately, epilepsy, or at least a few rarer forms of epilepsy, have a tendency to develop in adolescents. The Food and Drug Administration, as you might have guessed, is particularly protective of adolescents, considering the vast array of negative studies on marijuana use among teens and the fact that few positive long-term studies currently exist. Studies like the one conducted by the University of Colorado at Boulder could help change the FDA's tune.

Source: GW Pharmaceuticals.

One cannabinoid-based therapy currently working its way through clinical trials is Epidiolex from GW Pharmaceuticals . Epidiolex is being tested as a treatment for two rare forms of epilepsy, Dravet syndrome and Lennox-Gastaut syndrome. In earlier studies, Epidiolex reduced seizure frequency by 56% after 12 weeks for Dravet syndrome patients, and 52% for drop seizure patients, which are a common symptom for Lennox-Gastaut patients. If there's reduced fear about brain volume or shape impairment from using marijuana, we could see drug developers like GW Pharmaceuticals target diseases afflicting adolescents with greater frequency.

No smoking gunHowever, studies like this also demonstrate that there is no smoking gun for marijuana as of yet that definitively proves it's a benefit or risk to users. What this ultimately means is broader and longer-term studies will be needed to concretely sway the evidence in one direction or the other.

It also means that investing in marijuana stocks might as well be equated to buying a lottery ticket. While marijuana's market potential is large if additional states agree to legalize it recreationally and/or medically, there aren't very many ways of safely taking advantage of that growth in the stock market. What marijuana stocks are available for purchase lack a business plan older than two years and, in many cases, a profit. In instances like GW Pharmaceuticals, where we have a legitimate company trading on a reputable exchange, we still have years to go before profitability is even plausible.

As continues to be the case, marijuana studies will roll in, but in my opinion, the investment itself is still worth avoiding at all costs.

The article Could This New Marijuana Study Smoke Pessimists? originally appeared on

Sean Williamshas no material interest in any companies mentioned in this article. You can follow him on CAPS under the screen nameTMFUltraLong, track every pick he makes under the screen nameTrackUltraLong, and check him out on Twitter, where he goes by the handle@TMFUltraLong.The Motley Fool has no position in any of the stocks mentioned. Try any of our Foolish newsletter servicesfree for 30 days. We Fools don't all hold the same opinions, but we all believe thatconsidering a diverse range of insightsmakes us better investors. The Motley Fool has adisclosure policy.

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