Marijuana is a mixture of dried flowers from the plant species Cannabis sativa and is the most commonly used illicit psychoactive substance worldwide (UNODC World Drug Report 2020). Though it is commonly believed to be a relatively harmless substance, there are many potential adverse consequences to using the drug, including addiction, withdrawal, and abuse in the form of a condition called Cannabis Use Disorder. Despite this, public perceptions of marijuana in recent years have shifted towards growing acceptance, and recent initiatives to legalize of the drug that have been successful in several states in the U.S. (Carliner, Prev Med, 2017; Pain, Nature, 2015). Paralleling marijuana’s changing reputation in the public sphere, however, are changes in how it’s used and, in its potency, both of which have increased over the past decade.
How Common is Marijuana Use?
Marijuana the most commonly used illicit substance worldwide, its prevalence of use is on the rise. In 2018, marijuana was used by an estimated 192 million people worldwide, which corresponded to a 16% global increase since 2006. This increase was most pronounced in the United States, where 8.8% of the population aged 15 through 64 years of age uses marijuana in some form (UNODC World Drug Report 2020).
Not only has the total number of people who use marijuana increased—its frequency of consumption has evolved as well. The hard truth is that people are smoking more often than they used to. In the United States, the number of daily or almost-daily users doubled between 2009 and 2018, and the number of people who used the drug at least once in the past month increased by two-fold (UNODC World Drug Report 2020). In 2018, 4.7% of the US population aged 18 and older (around 11.6 million people) were estimated to be daily or nearly daily users of marijuana; by comparison, about 1% of the population in Western in Central Europe use marijuana at this frequency, highlighting differences in usage between populations.
Who makes up this group of people who use marijuana? Increases in use of the drug has been observed across all genders, geographic regions, and educational and employment statuses. Higher rates of use, though, are more likely to be seen in men and unemployed individuals (Hasin, Neuropsychopharmacology, 2017), as well as in Americans and Canadians compared to people from other countries. Young adults in particular seem to make up the largest proportion of frequent marijuana users–in the United States, the highest proportion of people who had used marijuana in the past month was in people aged 19-25 years of age (20.8%) followed by those aged 26-35 (16.4%) (UNODC World Drug Report 2020).
High Potency Marijuana
As marijuana has gained popularity and generalized acceptance across the globe, high potency marijuana has emerged as an increasingly available option that has contributed to intensification of marijuana use.
Marijuana is composed of a combination of compounds that are collectively referred to as cannabinoids: cannabidiol, or CBD, and tetrahydro-cannabidiol, or THC. THC is the primary psychoactive component of marijuana, whereas CBD is thought to be responsible for the many physical symptoms you might experience when you use. When we talk about potency, we’re referring to the ratio of THC to CBD. This ratio is primarily what dictates the psychoactive strength of the strain of marijuana you’re consuming, with higher THC:CBD ratios corresponding to more mind-altering effects.
Over the past 40 years, marijuana potency has approximately doubled worldwide (Cascini, Curr Drug Abuse Rev, 2012; WHO, Cannabis, 2016). In the United States, chemical analysis of marijuana potency from samples confiscated by the Drug Enforcement Administration have shown that the average concentration of THC increased from about 4% in 1995 to 17% in 2017 (ElSohly, Biol Psychiatry, 2016; Chandra, Eur Arch Psychiatry Clin Neurosci, 2019). Meanwhile, the CBD content of marijuana strains has actually decreased, from an average of 0.28% in 2001 to less than 0.15% in 2014. The end result is that marijuana’s average THC:CBD ratio has increased from approximately 14 to 80 from 1995 to 2014 alone (ElSohly, Biol Psychiatry, 2016). So, while research has shown that CBD can actually offset some of THC’s more harmful effects, like memory impairment and psychotic-like symptoms, shifts in marijuana’s chemical makeup mean that the marijuana you may consume today is much more likely to cause unpleasant side effects (Englund, J Psychopharmacol, 2013).
A growing body of research implicates high potency marijuana as being associated with negative health outcomes, including increased symptoms of cannabis use disorder (Freeman, Psychol Med, 2015), increased admission for specialist drug treatment (Freeman, Psychol Med, 2018), and higher risk of developing psychosis (Di Forti, Lancet Psychiatry, 2015). Needless to say, increased potency of available marijuana strains has important implications for your health. If you decide to use, pay special attention to the potency of the strain, so that you are aware of likelihood of adverse effects.
How Is Marijuana Consumed?
One of the most common ways that people use marijuana is by smoking it, either in the form of rolled cigarettes (“joints”) or in bongs. The main mind-altering substance in marijuana, THC, can also be extracted using various organic chemical solvents in order to create highly concentrated marijuana products containing as much as 60-99% THC by weight. They can then be smoked in a variety of forms including “wax”, “dabs”, “budder” or “shatters” (Loflin, Addict Behav, 2014).
Highly concentrated marijuana products can also be consumed via inhalation of distilled marijuana oils. The more common name for this method of marijuana use is ‘vaping’. This process entails converting a highly concentrated liquid form of marijuana into a vapor, typically using a vaporizing device (which appears similar to an electronic cigarette). Puffing on the device activates a battery-powered heater that vaporizes the marijuana liquid into a vapor that is subsequently inhaled (Morean, Pediatrics, 2015).
Highly concentrated marijuana products can also be mixed into food products such as brownies, candies, and beverages. When directly ingested, edible marijuana also produces a high similar to smoking or vaping but takes longer to kick in because it must first be absorbed through your digestive tract. In contrast, smoking or vaping allows marijuana near immediate access into your bloodstream, via the blood vessels that collect oxygen from your lungs.
Discrete Marijuana Use
As alternative methods of marijuana use become more readily available, there has been a growing trend towards increasingly discrete forms of marijuana use, namely vaping and eating edibles. Although it may be more socially acceptable to use marijuana in these forms in public, there can be unanticipated risks associated with these more subtle forms of marijuana use, including using more frequently throughout the day.