1. Is Cannabis Addictive?

Unfortunately, this question can’t be answered with a straightforward yes or no. A divisive topic, whether or not cannabis is addictive often comes down to how “addiction” is defined.

In the same way that food, gambling or sex might be considered addictive, cannabis could arguably be considered psychologically addicting due to the enjoyable brain responses it produces. However, if your definition surrounds chemical dependence characterized by withdrawal symptoms, cannabis is not addictive.

In the scientific and medical communities, experts don’t refer to “cannabis addiction.” Instead, the term “cannabis use disorder (CUD)” is much more common. According to the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders, there are 11 indicators of cannabis use disorder:

  • Cannabis is often taken in larger amounts or over a longer period than was intended
  • There is a persistent desire or unsuccessful efforts to cut down or control cannabis use
  • A great deal of time is spent in activities necessary to obtain cannabis, use cannabis, or recover from its effects
  • Craving, or a strong desire or urge to use cannabis
  • Recurrent cannabis use resulting in a failure to fulfill major role obligations at work, school, or home
  • Continued cannabis use despite having persistent or recurrent social or interpersonal problems caused or exacerbated by the effects of cannabis
  • Important social, occupational, or recreational activities are given up or reduced because of cannabis use
  • Recurrent cannabis use in situations in which it is physically hazardous
  • Cannabis use is continued despite knowledge of having a persistent or recurrent physical or psychological problem that is likely to have been caused or exacerbated by cannabis
  • Tolerance, as defined by either a (1) need for markedly increased cannabis to achieve intoxication or desired effect or (2) markedly diminished effect with continued use of the same amount of the substance
  • Withdrawal, as manifested by either (1) the characteristic withdrawal syndrome for cannabis or (2) cannabis is taken to relieve or avoid withdrawal symptoms

While cannabis can enrich lives and be healing for many users when used responsibly and in moderation, there is a minority of regular cannabis users who may have CUD, which takes the form of “addiction” in severe cases. Those cases include when an individual cannot stop using even though it interferes with many aspects of their life.

However, the majority of the general public is not susceptible to becoming “addicted” to cannabis because a typical cannabis consumer’s behaviors aren’t in line with the above indicators, making dependency resulting in negative life-altering consequences incredibly rare.

So, in short, is cannabis addictive? It’s complicated…

2. Does cannabis affect your IQ? Esp. for younger users?

Because of cannabis’ federally illegal status, it remains difficult for researchers to rigorously study its long-term impacts. While one documented consequence is short-lived interference with memory, far less documented, however, is whether cannabis has lasting effects on cognitive abilities, including one’s intelligence quotient (IQ).

One 2012 report from New Zealand recorded participants’ use of the drug from their early teen years through their 30s, showing slight IQ increases over time among those who never used marijuana, while other users experienced steady IQ declines proportional to how long they had smoked and how much. Those who smoked marijuana heavily as adolescents and later quit never fully returned to the baseline, and those who had used cannabis most persistently had an overall decline of around six to eight IQ points.

But that study doesn’t paint the full picture because each participant acts as his or her own control. Enter twin designs. Because twins grow up with the same family backgrounds and are genetically very similar, they serve as ideal experimental controls for each other.

In two longitudinal studies of adolescent twins in California and Minnesota, researchers measured the twins’ intelligence between nine and 12 years of age, before any drug use, and did so again between ages 17 and 20. While marijuana users had lower test scores and showed notable reductions in IQ over time, analysis revealed that marijuana use and IQ were completely uncorrelated — and IQ measures fell equally in both the users and abstainers. Subsequent twin studies corroborated these findings of no relationship between marijuana use and a falling IQ.

When it comes to young people using, some data has indicated that the adolescent brain may be most vulnerable in terms of neurocognitive function. Though marijuana use has been linked to decreased memory, lower verbal ability and diminished attention, these associations are based on cross-sectional studies in which the temporal orders of cause and effect are unclear.

Plus, young marijuana users are much more likely to also use alcohol and other illicit drugs. So, when epidemiologists factor binge drinking, nicotine and other drug use into their models, marijuana’s cognitive effects evaporate. Thus, IQ decline seems more nonspecifically related to general substance use.

In the end, declines in adolescent IQ may not be due to cannabis use but rather familial factors that set the stage for cannabis initiation and decreased intellectual attainment. Overall, the research remains spotty when it comes to cannabis and intelligence. While it is clear that cannabis can influence memory in the short term, long-term marijuana use is still questionable, as we lack proper longitudinal research that accounts for all outside influence.

3. I heard cannabis is much stronger now than back in my day. Is that true?

Many people believe that cannabis is much stronger than it used to be.

While sensational headlines might note that today’s marijuana is three times as potent as it was in the 1980s or far stronger than it was 20 years ago, those reports relied on the outdated — and likely inaccurate — statistic that old-school cannabis had tetrahydrocannbinol (THC) concentrations of 10% or less. As the Atlantic reported in 2015, the federal data that figure is based upon is incomplete, and the information we do have about cannabis from back in the day may be full of inaccuracies — the cannabis could have mostly come from a single region or a specific grower, skewing the THC results.

The notion that pot has increased dramatically in potency is a DEA myth based on biased government data. When carefully examined, that government data shows that average marijuana potency increased modestly by a factor of two or so during the seventies — and has been more or less constant since then.

Today, legal market for cannabis opens the door for more variety than ever before: you can both find cannabis that is high in CBD with THC concentrations of just 1% or less as well as cannabis strains bred to be stronger and higher in THC levels. However, it is important to note that a strain’s potency isn’t fixed but fluctuates according to growing conditions and cultivation methods.

The most potent cannabis at your local dispensary likely tops out in the mid-20% THC range, and the overall THC average for a legal market tends to be lower still: For example, Colorado’s THC average is just 18.7%.

Although it is that true modern cannabis contains higher levels of THC, it is important to note the drastic changes, improvements and agricultural advances that have been made specifically to improve the cannabis plant. Over the years, cannabis cultivators began creating near perfect conditions for the plant to thrive and maintain high levels of THC throughout the various stages of flowering. In addition to closely monitored grow rooms (temperature, humidity, light value), growers have turned to fine-tuned genetics by crossbreeding successful strains to create new selections. The process of creating new strains was historically an underground operation unlike today where breeders celebrate their process publicly, and legally.

At the end of the day, “stronger” cannabis is more widely available today than ever before. When the discussion centers around cannabis being “stronger” today than a few decades ago, what we’re really talking about is how cannabis went from being an illicit commodity to a regulated national business.

4. Is it true that cannabis users are younger than ever before?

After alcohol, cannabis is the most commonly used “drug” in the U.S. — and its use is growing as an increasing number of states legalize recreational and medical cannabis.

Based on a representative sample size from 1,000-plus dispensary locations, THC buyers are now coming from all ages and all walks of life. While use was most frequent in states where cannabis laws had been passed, studies illustrate that use did not significantly differ before and after the laws were passed. One study’s findings suggest that the passage of state medical marijuana laws “does not increase adolescent use of marijuana,” but that “adolescent use is higher in states that ever passed such a law than in other states.”

Plus, a recent release of a massive federal drug use survey shows monthly marijuana use has skyrocketed among older Americans. Now, Americans ages 55 to 64 are now slightly more likely to smoke marijuana on a monthly basis than teens ages 12 to 17, and seniors age 65 and older have seen steep increases in cannabis use as well. While the millennial generation is the largest segment of both recreational and medical 2020 cannabis sales by generation, millennials account for less than half of sales in both categories. And since the mid-2000s, past-month cannabis use has actually slightly decreased in 12- to 17-year-olds.

So, no, cannabis users are not younger than ever before — they’re about the same age as they always have been if not slightly older.

5. Does marijuana harm young bodies and minds?

Prohibitionists often argue that cannabis “harms the developing brains of young people.” But is that true?

On one hand, heavy marijuana use in adolescence or early adulthood has been associated with a dismal set of life outcomes, including poor school performance, higher dropout rates, increased welfare dependence, greater unemployment and lower life satisfaction, but on the other hand, it’s not clear that cannabis deserves the bulk of the blame. From peer influence to emotional distress or a tendency toward problem behavior, myriad other factors could predispose people to drug use and poor life outcomes.

Unfortunately, we just don’t have the rigorous research to provide a concrete answer one way or the other. Although a number of studies have found evidence of brain changes in teens and young adults who smoke marijuana, other studies have failed to turn up evidence that marijuana use results in brain abnormalities and harm to the brain.

Additionally, most of the research on the long-term cognitive effects of cannabis focuses on heavy users, so it’s unclear whether there’s a safe level of use nor is it known whether any brain changes associated with cannabis use are permanent or if the brain can recover with time.

To sum it up, the evidence for cannabis harming young bodies and minds is frustratingly mixed. While some studies have found increased risk for mood disorders and psychotic symptoms among marijuana users, other studies found that chronic use among teenage boys did not raise the risk of later depression, lung cancer, asthma or psychotic symptoms.