Image source: Pixabay.

Marijuana has been something of an unstoppable force over the past two decades. After being completely outlawed in all states in 1995, marijuana in 2015 can now be legally sold in 23 states for medicinal purposes (as well as Washington, D.C.), and it can be sold legally for recreational use to adults ages 21 and up in four states (and Washington, D.C.).

A big component of this sweeping change is the rapid shift in public opinion as well as the need for states to generate revenue. Over the past two decades, respondents in Gallup's marijuana polls have pushed their favorability of the drug from a mere 25% to more than 50% on a consistent basis in recent years. As the negativity surrounding marijuana has lessened, the push for experimentation into its possible medical benefits, and the desire to use marijuana without potential federal consequences, has intensified.

States have also played a big role in marijuana's recent proliferation. Along with the desire to follow the sentiment of their constituents, many states' elected officials are desperate for new sources of revenue. Raising taxes on an entire constituency is often not a path to reelection. Taxing marijuana, though, pulls in extra revenue from a defined consumer base and industry, while leaving a majority of residents unaffected by the new tax. This extra revenue can be used to create or maintain jobs, or as is the case in Colorado, to possibly support the education system. Colorado residents will vote very soon on what should be done with the tax revenue generated from marijuana sales.


Image source: Flickr user Cannabis Culture.

Do we have a marijuana problem on our hands?
As marijuana sales have grown, concern about marijuana's proliferation has grown as well. A study released a little more than a week ago in JAMA Psychiatry subtly implies that we may very well have the beginnings of a marijuana problem on our hands if we don't educate consumers.

The study, which was authored by a dozen researchers, sought to examine what changes we've witnessed in marijuana use prevalence rates over the past decade. Additionally, it sought to examine trends in marijuana use disorders, which are defined as abuse or dependence on the drug. Marijuana use disorders can lead to comorbidities and disabilities, which have the potential to strain an already thin U.S. healthcare network.

Researchers used data of U.S. adults compiled in two separate surveys. The first included face-to-face interviews of 43,093 adults between April 2001 and April 2002, and the second involved face-to-face interviews of 36,309 adults between April 2012 and June 2013.

Image source: National Drug and Alcohol Research Centre.

What researchers discovered was that marijuana use prevalence and marijuana use disorder prevalence had both risen over the prior decade. Past-year use prevalence in the 2001-2002 period was just 4.1%. By the 2012-2013 period, this had more than doubled to 9.5%.

The rise in marijuana use disorder prevalence was a bit less straightforward. In terms of the percentage of marijuana users exhibiting abuse of or dependence on the drug, it actually dropped from 35.6% in 2001-2002 to 30.6% in 2012-2013. However, the total number of users exhibiting a marijuana use disorder as a whole is up over the prior decade simply because of the sheer increase in marijuana use among respondents. Additionally, the prevalence of a diagnosis of a past-year marijuana use disorder rose from 1.5% in 2001-2002 to 2.9% in 2012-2013.

Based on marijuana's growing prevalence, researchers suggest that consumers, physicians, and lawmakers be educated about the potential harms of marijuana use, as well as the propensity for addiction to the drug. Researchers note that clearly not all of marijuana users will become addicted, but the data suggests that around three in 10 will.

Marijuana's federal roadblock
The truth is, studies just like this one help to reinforce many of the roadblocks currently in place within the federal government that'll keep Congress from changing its stance on marijuana anytime soon.

Perhaps the biggest roadblock of all is the long-term safety profile of marijuana. Don't get me wrong, we've witnessed numerous instances of marijuana providing medical benefits in somewhat recent clinical studies. Marijuana has been shown to create positive benefits in treating epilepsy, type 2 diabetes, Alzheimer's disease, Parkinson's disease, and aggressive forms of brain cancer.

Image source: White House on Flickr.

However, marijuana also has a mound of clinical studies stacked a mile high detailing harmful side effects. A lot of this imbalance has to do with marijuana studies centering on its risks rather than its benefits for multiple decades. Only within the past decade or so have researchers really begun to turn their attention to the drug's possible benefits. The problem is that it takes time for these long-term benefit studies to mature, and one study is not enough on its own to establish safety. Each study is like a puzzle piece that helps set the stage for lawmakers regarding marijuana's safety profile -- and it's going to be years before that puzzle is even fully framed!

Another issue is that the federal government appears somewhat apathetic toward the marijuana movement. It's a bit of a head-scratcher considering the slim majority of respondents that support marijuana in a number of national polls, but as President Obama suggested earlier this year, the youth of America should be focused on far more important issues than marijuana. Both President Obama and Congress have made it a point to emphasize economic and job growth, as well as national security, while de-emphasizing the debate over marijuana.

What this means for you is that marijuana is unlikely to become the "next big thing" anytime soon, even though the market potential for marijuana is much, much bigger than we're seeing today. With Congress having little incentive to alter its perception of marijuana, it very well could mean that marijuana-based businesses could lose money or struggle to survive in the meantime.

My suggestion, as it's remained all along, is to keep your money squarely on the sidelines and away from the marijuana industry until we witness a definitive change in policy from the federal government.

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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